The Scientific World Journal

The Scientific World Journal / 2014 / Article

Research Article | Open Access

Volume 2014 |Article ID 723280 | 27 pages | https://doi.org/10.1155/2014/723280

Work-Related Health Disorders among Saudi Computer Users

Academic Editor: Pasquale Aragona
Received26 Jan 2014
Revised09 Jul 2014
Accepted07 Aug 2014
Published14 Oct 2014

Abstract

The present study was conducted to investigate the prevalence of musculoskeletal disorders and eye and vision complaints among the computer users of King Abdulaziz University (KAU), Saudi Arabian Airlines (SAUDIA), and Saudi Telecom Company (STC). Stratified random samples of the work stations and operators at each of the studied institutions were selected and the ergonomics of the work stations were assessed and the operators’ health complaints were investigated. The average ergonomic score of the studied work station at STC, KAU, and SAUDIA was 81.5%, 73.3%, and 70.3, respectively. Most of the examined operators use computers daily for ≤ 7 hours, yet they had some average incidences of general complaints (e.g., headache, body fatigue, and lack of concentration) and relatively high level of incidences of eye and vision complaints and musculoskeletal complaints. The incidences of the complaints have been found to increase with the (a) decrease in work station ergonomic score, (b) progress of age and duration of employment, (c) smoking, (d) use of computers, (e) lack of work satisfaction, and (f) history of operators’ previous ailments. It has been recommended to improve the ergonomics of the work stations, set up training programs, and conduct preplacement and periodical examinations for operators.

1. Introduction

The one thing that has had the greatest impact on our lives in modern time is the computer. Along with smaller size and affordable prices, there has been the advent of the Internet. This has ensured that people use this technology either at their work place or at home. Meanwhile, the applications of computer technology and the accompanying use of video display terminals (VDTs) are revolutionizing the workplaces worldwide, and their use will continue to grow in the future.

Although these developments may perform operators’ tasks efficiently, they could face some factors such as work stress, repetitious tasks, boredom, interpersonal factors, unsafe postures, and poor design of workstation that will negatively affect their health, performance, and productivity. For example, the development of VDTs technology may have contributed to the increase of users’ health problems such as cumulative trauma disorders (CTDs) of upper extremity and back pain [154] as well as vision problems [111, 13, 14, 19, 20, 26, 44, 45, 5153, 5584].

However, the application of ergonomics principles to office workstations will reduce such health risks. For example, one of the goals of the ergonomic processes is to design or modify people’s work and other activities to be within their capabilities and limitations [3, 57, 12, 1517, 22, 23, 2830, 38, 4446, 8588]. One possible outcome of poor harmonization is disorder of the musculoskeletal system known as repetitive strain injuries (RSI), CTD, or activity and work-related musculoskeletal disorder (WMSD). Those working in office-type jobs involving keyboarding and other computer related activities suffer from these disorders [9, 13, 1518, 2224, 28, 33, 42, 50, 88].

Currently computer related injuries are developing into an epidemic among computer users. It is estimated that, worldwide, 25% of computer users are already suffering from computer related injuries [35]. The United States has to shell out more than 2 billion US dollars annually for having ignored these computer related problems. It is now proved that the duration of work and computer-related problems are positively correlated. It is not uncommon these days for people having to leave computer dependent careers or even be permanently disabled and unable to perform tasks such as driving or dressing themselves. Occupationally caused RSI rank first among the health problems potentially affecting the quality of life [89]. Meanwhile, poor workstation design and poor ergonomics have been associated with an increased risk of developing these disorders.

The tremendous use of computer by the staff members, technicians, and students at King Abdulaziz University (KAU), by our experience, has been accompanied by increase in the number of attendances to University Medical Directorate (Services) with general, eye and vision, and musculoskeletal complaints. When this observation was brought to the attention of KAU officials, they urged and encouraged concerned personnel to study the nature of this problem and propose remedial actions.

Meanwhile, one of the first institutions that had applied computer technology in Saudi Arabia was the Saudi Airlines tickets’ reservation offices (SAUDIA). It is considered to be one of most eligible areas to conduct a study regarding VDT health related problems. Putting this in mind, KAU urged concerned personnel to include it in the present study. Also, the Saudi Telecom Company (STC) works in Jeddah comprises nearly 430 VDT workstations where 360 operators and mostly 70 supervisors work for whole shifts. There have been some claims that these operators and supervisors suffer some general musculoskeletal and eye and vision complaints. Consequently, these works have been decided to be included in this study.

The objectives of the present study were(1)to evaluate the magnitude of the problem of inconveniences in the use of computers in KAU, SAUDIA, and STC, as well as the inconveniences in the computers’ workstations,(2)to investigate computers’ operators health complaints,(3)to investigate environmental and behavioral factors contributing to the occurrence of the complaints,(4)to propose remedial actions that might contribute to reducing these complaints.

2. Methodology

2.1. Study Population

Inventories of the computer workstations and operators in the different colleges and units of KAU, in the different departments and units of SAUDIA tickets’ reservation offices, and in the different departments and units of STC head office in Jeddah had, primarily, been conducted to assess the magnitude of computer use there. The findings of the inventories are summarized in Table 1.


InstitutionUnitsExisting serviceSample
WorkstationSupervisorOperatorWorkstationSupervisorOperator

King
Abdulaziz
University
(KAU)
(i) Higher administration, including
Deanship of Admission and
Registration and Deanship of
Student Affairs
30114
(ii) Deanship of Information
Technology
11416
(iii) Deanship of Library Affairs73
(iv) Faculty of Economics and
Administration
969
(v) Faculty of Sciences869
(vi) Faculty of Engineering13016
(vii) Faculty of Medicine and University Hospital3417
(viii) Faculty of Arts and Humanities8114
(ix) Faculty of Earth Sciences635
(x) Faculty of Environmental Designs41
(xi) Faculty of Marine Sciences8
(xii) Faculty of Meteorology,
Environment and Arid Land Agriculture
16
Total1043100

Saudi Airlines
Ticket
Reservation
(SAUDIA)
(i) Central Control for Africa and Europe Flights2015
(ii) Central Control for Local and Gulf Flights2015
(iii) Central Control for Asia and Middle East Flights105
(iv) Record and Follow-up Department2010
(v) Customer Services Department16555
Total235100

Saudi Telecom
Company
(STC)
(i) English Call Services Department1590416
(ii) Help Services Department24120827
(iii) Other Services Department301501035
Total693602278

Representative random samples of 100 workstations, and operators (all males, since no females are employed there), were selected from each of the three institutions, considering that the selection of the sampled stations and operators had been affected by the readiness of the individual administrations and operators in the different departments and units to participate in the study. The selected stations are also presented in Table 1.

2.2. Studying Ergonomics of Workstations

A study form entitled “Ergonomics Rating of Computer Applications” was developed to assess the ergonomics status of the studied computer workstations. The form was designed after reviewing the ANS/HFES Committee document [6], and many computer’s workstation evaluation checklists that had been tested and used by international institutions include(1)U.S. Department of Health and Human Services, Centers of Disease Control, and Prevention (CDC), Evaluation Checklist;(2)National Institute for Occupation Safety and Health (NIOSH) Ergonomics Work-Place Evaluations of Musculoskeletal Disorders Checklist;(3)U.S. Department of Labor, Occupational Safety, and Health Agency (OSHA) Computer Workstation Ergonomic Checklist;(4)University of California Computer Workstation Self-Evaluation Checklist;(5)California State University Ergonomics Evaluation Checklist;(6)Cornell University Ergonomics Checklist;(7)University of Virginia Library Ergonomics Evaluation Form;(8)Institute for Occupational Physiology at the University of Dortmund Checklist for Computer Workstation;(9)Atlantic Mutual Centennial Insurance Company Workstation Checklist.

The ergonomics score for the evaluation of the workstation is 43, distributed by the different components. Each component has certain number of scores, determining the maximum score of the component as shown in Table 2. Besides, 3 scores are allowed for the work organization and 4 scores for the training and provision of information, making a total score for the work at the specific workstation of 50, which is equivalent to 100% when scoring percentagewise.


Workstation componentMaximum score

(1) Desk5
(2) Seat6
(3) Footrest1
(4) Display screen8
(5) Keyboard3
(6) Mouse3
(7) Document holder2
(8) Space and room layout7
(9) Task and posture2
(10) Illumination4
(11) Noise and thermal environment2

Total scores43

Each score item is clearly presented to be answered by “Yes” or “No” to avoid any personal differences or any bias by the evaluators. The “Yes” answers are counted to represent the score out of 50, and some ten stations were evaluated to test the study from and found to be satisfactory for the conduct of the study. Furthermore, the evaluation of the workstations was carried out, only, by the authors for quality assurance of the data collection. The study form has been designed in four major sections including the following.

Section (1). It includes basic information of investigated organizations (colleges/units), particularly as related to presented services.

Section (2). It includes ergonomics rating of investigated workstations by checking the details of each component of the work place, including(1)desk, as related to space of desk top, layout of the desk, top equipment, desk top and distance from operator’s eye, and existence of comfortable resting facility for operators’ hands and rest;(2)seat, as related to dimensions, casters, operators’ leg clearance, armrests, back rest, seat cushion, and seat comfort ability and stability;(3)footrest, as related to need, availability, and status of footrest;(4)display screen, as related to location, height and tilting of the monitor, distance from operator’s eye, freedom of screen from glare and reflection, stability of image and freedom from flickering, ease to read characters, and possibility of adjusting screen brightness and contrast;(5)keyboard, as related to dimensions, location with reference to operator’s hands and elbows, and exchanging operation between keyboard and mouse without operator’s hand extension or twisting wrist;(6)mouse, as related to its location with reference to operator smooth running and operator’s awareness of its details of operation and maintenance;(7)document holder, as related to need, availability, and status of the document holder;(8)space and room layout, as related to adequate access to work place, availability of space to maneuver the seat, work correct posture, availability of adequate space for equipment needed for work, location of monitor with reference to windows, freedom of work area from obstructions, and hazards of tripping and neatness of the work area;(9)task and posture, as related to freedom of operator’s hands from phone while typing and resting his hand wrists;(10)illumination, as related to level of lighting, status of luminaries and illumination fixtures, use of blinds on windows, and background of the screen with surrounding environment;(11)noise and thermal environment, as related to level of quietness and status of air conditioning in work area.

Section (3). It includes work organization rating, by investigating work organization, work hours, rest pauses and noncomputer work assignment, and work load.

Section (4). It includes training and provision of information, by investigating operator’s on-the-job and formal training, certainty of his use of software, keying habits, operator’s capability of control of his workstation and work environment, and operator’s adoption of good posture and avoiding visual fatigue at work.

2.3. Investigating Operators’ Health Symptoms

A study form entitled “Impact of Computer Use on Operators” was developed to evaluate the effect of computer use on operator’s health as reviewed and/or recommended by the NIOSH [1], WHO [5], and ANSI/HFES [6]. It is divided into four main sections as follows.

Section (1). It includes basic data, including name, gender, address, workstation, age, education, and smoking habit.

Section (2). It includes work data, including work type, duration of employment, formal training, work speed, daily hours of computer use, nature of computer use (continuous or intermittent), and work satisfaction.

Section (3). It includes health disorders before present work, including previous ailments or complaints of the musculoskeletal system and complaints of the eye and vision.

Section (4). It includes current symptoms, including the general complaints and their frequency, the eye and vision symptoms and their frequency, the maximum work hours before their occurrence and the time required for their release, and the musculoskeletal disorders and their location, description, frequency, and persistence, as well as the approached medical treatment and the sickness absenteeism as related to the work-related ailments.

2.4. Data Analysis

The collected data were visually inspected for fliers, then introduced into PC, and subjected to statistical analysis using Microsoft Excel 2007.

3. Results and Discussion

3.1. Ergonomics of the Workstations

The ergonomics scores of the studied workstations in the three institutions are illustrated in Table 3 and Figures 1 and 2. The average workstations score in STC has been rated very good which is considerably higher than the scores of both KAU and SAUDIA ( and , resp.) (Figure 2). This might be attributed to the relatively recent establishment of the workstations in STC in comparison to the other two study locations (KAU and SAUDIA). However, the score of the different components varies considerably in the three locations. For example, task and posture has been rated 95% and 90% at STC and SAUDIA, respectively, while it has been the lowest scored component at KAU (54%). Also, work organization has been rated the second highest (98.3%) at SAUDIA while it has been rated the second lowest at KAU (57.7%) and in the middle of the scores at SAUDIA (73.2%). These variations might be attributed to the differences of the type of work and pattern of computer use at the different study locations. The distribution of the ergonomics scores of the examined workstations might be considered to follow normal model but truncated (Figure 2).


NumberErgonomics componentsKAU* ( = 100)SAUDIA** ( = 100)STC*** ( = 100)
Number of positivesAverageNumber of positivesAverageNumber of positivesAverage

INoise and thermal environment
 1 Quietness7584.07881.58386.5
 2 Air-conditioning938590

IIDisplay screen
 3 Monitor location7180.47075.49787.4
 4 Monitor top8010099
 5 Monitor distance from eye7110098
 6 Monitor tilting757297
 7 Glare and reflection686070
 8 Image stability916780
 9 Ease of reading956874
 10 Brightness and contrast926684

IIIDesk
 11 Space8178.410081.410099.4
 12 Layout858599
 13 Distance from eye7486100
 14 Room for leg9365100
 15 Hand/wrist597198

IVMouse
 16 Distance from hand8377.77571.37271.3
 17 Run767876
 18 Operator’s familiarity746166

VSeat
 19 Height8975.310074.79977.7
 20 Dimensions787295
 21 Armrest767577
 22 Backrest647959
 23 Pad (foam)716063
 24 Comfort and stability736273

VISpace and room layout
 25 Adequate access9073.76568.92478.7
 26 Space around seat86100100
 27 Layout806193
 28 Location of equipment626188
 29 Monitors’ positions5166100
 30 Obstructions and hazards7560100
 31 Housekeeping726946

VIIIllumination
 32 Lighting level9172.35548.86086.8
 33 Luminaries664699
 34 Effectiveness614397
 35 Background behind screens715191

VIIITraining and provision of information
 36 Use of software7571.54647.37660.3
 37 Habit keying735966
 38 Adjustment744365
 39 Good posture and visual fatigue644134

IXKeyboard
 40 Distance6969.76666.09895.0
 41 Width736975
 42 Height and key angle676392

XFootrest
 43 Compression of thigh6868.06565.05454.0

XIDocument holder
 44 Need6463.09090.03938.0
 45 Balance of head posture629037

XIIWork organization rating
 46 Breaks7959.710073.38889.3
 47 Urgent peaks and interruptions405583
 48 Over time606597

XIIITask and posture
 49 Phoning while typing3354.09095.09990.0
 50 Typing posture7510081
Total average score72.371.181.0

*KAU = King Abdulaziz University.
**SAUDIA = Saudi Airlines.
***STC = Saudi Telecom Company.
3.2. Characteristics of the Work Population

The demographic and occupational characteristics of the studied populations of the computer users/operators in the three institutions are presented in Tables 4 and 5. The populations at the different study locations were mostly young, since 98% of the subjects in both KAU and STC, and 89% at SAUDIA, were younger than 50 years. However, the subjects of the study population at SAUDIA were relatively older since 27% of them were younger than 35 years in comparison to 80% at STC and 68% at KAU (Table 4). The average ages at the KAU, SAUDIA, and STC were 31.5, 39.7, and 30.3 years, respectively. Yet 78% and 73% of the populations at STC and KAU have been employed for less than 10 years, in comparison to 23% at SAUDIA that began using VDT earlier than the other two institutions (Table 5). The average durations of employment at KAU, SAUDIA, and STC were 7.1, 19,7, and 7.4 years, respectively. Meanwhile, the levels of education among KAU and STC populations were higher than the SAUDIA population. For example, 65% and 41% of KAU and STC populations received higher education in comparison to only 23% at SAUDIA population. Also, 16% of the KAU and 5% of the STC populations, respectively, received graduate education (Doctor and/or Master), while none of the subject at SAUDIA population had such education level.


Demographic characteristicsFrequency
KAU ( = 100)SAUDIA ( = 100)STC ( = 100)

Age (years)
 20–2424919
 25–2930847
 30–34141014
 35–3915187
 40–4410208
 45–495243
 50–54292
 >55020
Education
 Middle622
 Secondary (general)217155
 Secondary (technical)842
 High (technical)19213
 High (administrative)302123
 Graduate (master + doctor)1605
Smoking index
Nonsmokers797662
 <1006517
 100–199329
 200–399245
 400–500533
 >6005104
Vision symptoms prior to present work*
None587058
 Short-sighted302325
 Long-sighted7210
 Others757
Musculoskeletal symptoms prior to present Work*
None596255
 Neck pain222417
 Shoulder and/or arms pain11114
 Lower trunk pain132316
 Thigh and leg pain584
 Others114

*The same subject might have more than one symptom occurring at different frequencies.

Occupational characteristicsFrequency
KAU ( = 100)SAUDIA ( = 100)STC ( = 100)

Duration of employment (years)
 <11277
 1-223524
 3-420417
 5–918730
 10–141175
 15–197149
 20–245205
 25–293163
 30–341160
 ≥35040
Type of work
 Data entry225433
 Data acquisition18239
 Typist2300
 Communication task82053
 Comprehensive office tasks2935
Duration of formal training (days)
On-the-job training only
586128
 <50121924
 50–995814
 100–19911220
 200–299424
 300–399441
 400–499301
 ≥500348
Work speed
 Fast393045
 Average567049
 Slow506
Computer use (hrs/day)
 31502
 41203
 5903
 62010053
 71401
 822017
 98021
Nature of daily work on computer
 Continuous615385
 Intermittent394715
Rest pauses of work shift (%)
 5–910012
 10–1422019
 15–1918016
 20–2419021
 25–29910010
 30–349011
 35–39706
 ≥40605
Elements of work satisfaction
 Satisfaction by foreman and colleagues interrelations1009999
 Satisfaction by absence work stress686061
 Satisfaction of work control969496
 Satisfaction of job attitude928182
 Satisfaction by vigilance requirement9410094
 Satisfaction by nature of work738555
 Satisfaction by absence of repetitive work and monotony593435
Evaluation of work satisfaction*
 Very satisfied393529
 Satisfied433731
 Satisfied to some extent101427
 Not satisfied81413

*Percent of duration(s) of rest pauses to duration of work shift.

Most of the study populations were nonsmokers (79%, 76%, and 62% of subjects at KAU, SAUDIA, and STC, resp.) and 26% of them at STC were light smoker (smoking index less than 200) that might be added to the proportion of the nonsmoker there to be 88%. This distribution might, however, be biased by the relatively young age of the examined subjects.

Considerable proportion of the populations either had no vision problems before employment (58%, 70%, and 58% at KAU, SAUDIA, and STC, resp.), or were short-sighted (30%, 23%, and 25%, resp.), while the rest were long-sighted or had other vision problems (14%, 7%, and 17%, resp.). Similarly, more than one half of the populations at the three study locations had no musculoskeletal symptoms before employment (59% at KAU, 62% at SAUDIA, and 55% at STC), while considerable proportions of the populations had neck pain (22% at KAU, 24% at SAUDIA, and 17% at STC). The rest of the populations had such symptom at one or more body locations.

More than one half of the population of KAU (52%) was either typist (23%) or involved in comprehensive office tasks (29%), while 40% of them were involved in data entry (22%) and data acquisition (22%). However, at SAUDIA, 77% of the populations were involved in data entry (54%) or data acquisition (23%) while 20% of them were involved in communication tasks and none of them was typist. Similarly, at STC, 86% of the populations were involved in communication tasks (53%) or data entry (33%), and none of them was typist. While 58% and 61% of the populations at KAU and SAUDIA, respectively, received on-the-job training only, and the rest received formal training for different periods, the opposite existed at STC, where 72% of the population received formal training for different periods, and only 28% of the population received on-the-job training only. Consequently, 61% of the populations at KAU and 70% at SAUDIA considered their work speed as average (56% and 70%, resp.) or slow (5% and 0%, resp.), while 45% of the population at STC considered their work speed as fast and 55% of them considered their work speed as either average (49%) or slow (6%).

Considerable proportions of the populations at KAU and STC used computer for 7, 8, or 9 hours per day (44% and 39%), while the whole population at SAUDIA (100%), and 53% of them at STC, used computer for 6 hours. On the other hand, 36% of the operators at KAU used computer for 3, 4, or 5 hrs. per day, while none of them at SAUDIA, and 9% of them at STC, operated computers for these shorter periods. However, only 53% of the SAUDIA population operated computer continuously in comparison to 85% of the STC and 61% of KAU populations. Meanwhile, mostly 70% of KAU (69%) and STC (68%) populations had rest pauses <25% of the work shift, and 22% of the two populations got rest pauses 30%–40% of the shift, while the whole SAUDIA population had 25%–29% of their shift as rest pauses, in comparison to 9% and 10% of the other two populations.

Eighty-two percent of the computer users in KAU, 72% of the operators at SAUDIA, and 60% of operators at STC were satisfied (and many were even very satisfied) at their work, particularly as related to their excellent satisfaction by their colleagues, work control, job attitude, and vigilance requirement, while the boredom from repetitive work and monotony and the work stress were the main causes of dissatisfaction among them, particularly the SAUDIA and STC populations (41%, 66%, and 65% at KAU, SAUDIA, and STC, resp.).

3.3. Operators’ Health Complaints

The operators’ health complaints are presented in Tables 69. Mostly one third of the operators (35%, 33%, and 27% of KAU, SAUDIA, and STC populations, resp.) was suffering from body fatigue, while 23%, 21%, and 37% of them were suffering from headache, such complaints occurred mostly sometimes among all the populations, however occurred to less extent, particularly among SAUDIA and STC operators. The lack of concentration occurred to less extent (for example, 8%, 6%, and 20% among KAU, SAUDIA, and STC populations, resp.), particularly and daily among SAUDIA and STC populations (Table 6).


SymptomsFrequency
KAU ( = 100)SAUDIA ( = 100)STC ( = 100)
NoneSome-timesOftenDailyTotal affected*NoneSome-timesOftenDailyTotal affected*NoneSome-timesOftenDailyTotal affected*

Headache7717602379116421632511137
General body fatigue6531403567171243373179127
Lack of concentration92710894132680108220
Total46459054602212640971113

*The same subject may have more than one symptom occurring at different frequencies.

SymptomsFrequency
KAU ( = 100)SAUDIA ( = 100)STC ( = 100)
NoneSome-timesOftenDailyTotal affected*NoneSome-timesOftenDailyTotal affected*NoneSome-timesOftenDailyTotal affected*

Eye
 Eye discomfort851230158884012917119
 Aches916309963104971203
 Pain954105952305925308
 Redness9162199081110935207
 Irritation and itching934307943306962204
 Burning8893012935207953205
 Tearing82144018923418917119
 Dryness963104925218963104
Vision
 Blurred: close objects926208933317953205
 Blurred: distant objects88930128685114916309
 Sensitivity to light8610311492341884142016
 Double flickering964004932417972103
 Double vision991001943216934307
 Change in color perception982002991001972103
 Others98110299010100000
All eye and vision symptoms414892596122125394614152554

*The same subject may have more than one symptom occurring at different frequencies.

SymptomsFrequency
KAU ( = 100)SAUDIA ( = 100)STC ( = 100)
NoneSome-timesOftenDailyTotal affected*NoneSome-timesOftenDailyTotal affected*NoneSome-timesOftenDailyTotal affected*

Aching731881278496116692010131
Tingling841150169352078993012
Numbness9351179225188847011
Burning953205980112961304
Paleness9900111000000991001
Swelling981012971113970303
Pain92233884862168468216
Stiffness9342179134298947011
Cramping981102961214981102
Total304717670492721351394710461

*The same subject may have more than one symptom occurring at different frequencies.

SymptomsFrequency
KAU ( = 100)SAUDIA ( = 100)STC ( = 100)
NoneOne  hrOne dayOne weekOne month to 1 yearTotal*NoneOne  hrOne dayOne weekOne month to 1 yearTotal*NoneOne  HrOne dayOne weekOne month to 1 yearTotal*

Neck786103322777104223811052219
Shoulder277135028751010142583863017
Arm and elbow8955011192150289711103
Forearm9116119904303109831002
Fingers8847011291250299134209
Higher back75716112582510211884385016
Lower back678192433829612187010145130
Buttock9702013875710139721003
Thigh9612104874702139333017
Knee9333017924310889452011
Leg932311794311169512205
Foot943111691440199412216
All symptoms3027309470492518445139232410461

*The symptoms may occur in more than one location at the same frequencies.

Only 41% and 46% of KAU and STC populations, in comparison to 61% of SAUDIA population, reported eye and vision symptoms. The most predominant eye symptoms were eye redness, tearing, pain, and redness, and the most predominant vision symptoms were blurring, particularly for distance objects, as well as sensitivity to light (Table 7).

Thirty percent, 49%, and 39% of the KAU, SAUDIA, and STC populations were free from musculoskeletal symptoms. The main occurring symptoms were aching, tingling, numbness, pain, and stiffness, which occurred, mostly sometimes, and, to a less extent, often (Table 8). The highest incidences of the symptoms were at the operators’ higher and lower back, neck and shoulder, arm, elbow, forearm, and fingers and then at the lower limbs (buttock to foot) (Table 9).

3.4. Factors Affecting Incidence of Complaints

The effects of age and duration of employment (i.e., work) on the incidence of operators’ health complaints are shown in Tables 10 and 11. There has been general trend of increasing the different complaints by age, particularly among those exceeding 35 years of age (Table 10). This observation is further confirmed in Table 11, where the operators working for >10 years had, generally, the highest incidences of the general and the eye and vision complaints, as well as the incidences of other complaints, but to a less extent.


Age (year) Number of
operators
Ergonomic score
mean (SD)
Duration of employment (year)
mean (SD)
Computer use
(hours/day)
mean (SD)
Complaints (%)
NoneGeneralEye and visionNeck and shoulderUpper extremityLower extremity Trunk

King Abdulaziz University computer users
20–29 5437.42.66.4724312616825
(5.0)(1.1)(1.5)(13.0)(44.4)(57.4)(48.1)(29.6)(14.8)(46.3)
30–39 2936.78.85.8517151612416
(6.3)(3.5)(2.0)(17.2)(58.6)(51.7)(55.2)(41.4)(13.8)(55.2)
40+ 1734.917.66.0310119437
(6.5)(7.2)(2.5)(17.6)(58.8)(64.7)(52.9)(23.5)(17.6)(41.2)

Saudi Airlines Ticket reservation operators
20–29 1769.12.06.04787438
(7.7)(1.3)(0.0)(23.5)(41.2)(47.1)(41.2)(23.5)(17.6)(47.1)
30–39 2871.614.96.011131010767
(11.0)(3.1)(0.0)(39.3)(46.4)(35.7)(35.7)(25.0)(21.4)(25.0)
40+ 5572.826.46.026202118111420
(13.6)(4.9)(0.0)(47.3)(36.4)(38.2)(32.7)(20.0)(25.5)(36.4)

Saudi Telecom Co. computer operators
20–29 6678.43.27.21240383419327
(9.8)(1.4)(1.6)(18.2)(60.6)(57.6)(51.5)(28.8)(48.5)(10.6)
30–39 2182.28.77.431413125106
(10.9)(3.1)(1.5)(14.3)(66.7)(61.9)(57.1)(12.4)(47.6)(28.6)
40+ 1395.921.66.61985280
(4.1)(3.2)(1.6)(7.7)(69.2)(61.5)(38.5)(15.4)(61.5)(0.0)


Duration of
employment
(year)
Number of
operators
Ergonomic score
mean (SD)
Age (year)
mean (SD)
Computer use
(hours/day)
mean (SD)
Complaints (%)
NoneGeneralEye and visionNeck and shoulderUpper extremityLower extremity Trunk

King Abdulaziz University computer users
≤2 3537.625.86.561417167414
(4.4)(2.7)(1.7)(17.1)(40.0)(48.6)(45.7)(20.0)(11.4)(40.0)
3–9 3836.229.36.4521222214622
(6.3)(3.5)(1.9)(13.2)(55.3)(57.9)(57.9)(36.8)(15.8)(57.9)
≤10 2736.442.35.8416181310512
(7.9)(4.5)(2.2)(14.8)(59.3)(66.7)(48.1)(37.0)(18.5)(44.4)

Saudi Airlines Ticket reservation operators
≤2 1269.723.36.03565235
(8.2)(1.6)(0.0)(25.0)(41.7)(50.0)(41.7)(16.7)(25.0)(41.7)
3–9 1168.930.66.04534214
(7.4)(2.1)(0.0)(36.4)(45.5)(27.3)(36.4)(18.2)(9.1)(36.4)
≤10 7771.943.16.034303026181925
(13.7)(2.9)(0.0)(44.2)(39.0)(39.0)(33.8)(23.4)(24.7)(32.5)

Saudi Telecom Co. computer operators
≤2 3176.725.27.261718179146
(13.5)(2.2)(1.9)(19.4)(54.8)(58.1)(54.8)(29.0)(45.2)(19.4)
3–9 4780.327.87.1828242113264
(7.7)(1.9)(1.5)(17.0)(59.6)(51.1)(44.7)(27.7)(55.3)(8.5)
≤10 2290.340.87.121817134103
(13.2)(5.4)(1.8)(9.1)(81.8)(77.3)(59.1)(18.2)(45.5)(13.6)

The impact of the ergonomics score of the workstation on the incidence of operators’ complaints is shown in Table 12, where there has been a trend of decrease in the incidence of operators’ general complaints, eye and vision complaints, and musculoskeletal complaints, particularly the extremities and the lower trunk complaints, by the increase of the ergonomics score of their workstations.


Ergonomic score Number of
operators
Age (year)
mean (SD)
Duration of employment (year)
mean (SD)
Computer use
(hours/day)
mean (SD)
Complaints (%)
NoneGeneralEye and visionNeck and shoulderUpper extremityLower extremity Trunk

King Abdulaziz University computer users
<601832.77.75.52111210958
(6.9)(4.3)(1.6)(11.1)(61.1)(66.7)(55.6)(50.0)(27.8)(44.4)
60–794131.77.26.5720221911721
(7.6)(6.1)(1.5)(17.1)(48.8)(48.8)(46.3)(26.8)(17.1)(51.2)
80+2730.16.56.1620262211419
(5.8)(4.4)(2.1)(14.6)(48.8)(63.4)(53.7)(26.8)(9.8)(46.3)

Saudi Airlines Ticket reservation operators
<602140.420.36.0810106448
(10.2)(11.4)(0.0)(38.1)(47.6)(47.6)(28.6)(19.0)(19.0)(38.1)
60–795738.918.46.023202021101421
(6.7)(7.9)(0.0)(40.4)(35.1)(35.1)(36.8)(17.5)(24.6)(36.8)
80+2240.05.56.0101098855
(4.5)(5.2)(0.0)(45.5)(45.5)(40.9)(36.4)(36.4)(22.7)(22.7)

Saudi Telecom Co. computer operators
<60626.13.67.81333243
(2.1)(2.8)(0.9)(16.7)(50.0)(50.0)(50.0)(33.3)(66.7)(50.0)
60–793527.03.86.8524191910198
(2.6)(2.0)(1.3)(14.3)(68.6)(54.3)(54.3)(28.6)(54.3)(22.9)
80+5931.98.87.2836372914272
(5.8)(5.8)(1.6)(13.6)(61.0)(62.7)(49.2)(23.7)(45.8)(3.4)

Out of the many factors considered for their effects on the incidences of the operators’ complaints and symptoms, the smoking habit, the type of work, workers satisfaction, and the operators’ history of musculoskeletal complaints and of eye and vision before joining present work showed some effects as indicated in Tables 1317. Smoking appears to have some effect on increasing the incidences of the general and eye and vision complaints, particularly among KAU computer users and SAUDIA operators, and on the lower extremities and lower trunk complaints, to some extent (Table 13).


Smoking
habit
Number of
operators
Ergonomic score
mean (SD)
Age (year)
mean (SD)
Duration of employment (year)
mean (SD)
Computer use
(hours/day)
mean (SD)
Complaints (%)
NoneGeneralEye and visionNeck and shoulderUpper extremityLower extremityTrunk

King Abdulaziz University computer users
Nonsmokers 7937.230.76.36.212372240241037
(7.6)(9.1)(6.6)(2.2)(15.2)(46.8)(27.8)(50.6)(30.4)(12.7)(46.8)
Smokers 2135.334.29.06.231417117511
(7.4)(9.3)(7.9)(3.1)(14.3)(66.7)(81.0)(52.4)(33.3)(23.8)(52.4)

Saudi Airlines Ticket Reservation operators
Nonsmokers 7572.239.518.96.032272621151521
(13.8)(9.1)(10.7)(0.0)(42.7)(36.0)(34.7)(28.0)(20.0)(20.0)(28.0)
Smokers 2569.040.420.96.091313147813
(10.4)(9.3)(9.9)(0.0)(36.0)(52.0)(52.0)(56.0)(28.0)(32.0)(52.0)

Saudi Telecom Co. computer operators
Nonsmokers 6281.829.06.77.0938353416338
(15.5)(6.5)(6.6)(2.1)(14.5)(61.3)(56.5)(54.8)(25.8)(53.2)(12.9)
Smokers 3881.030.37.58.7725241710175
(12.5)(8.4)(8.3)(8.6)(18.4)(65.8)(63.2)(44.7)(26.3)(44.7)(13.2)


Type of
work
Number of
operators
Ergonomic score
mean ± SD
Age (year)
mean ± SD
Duration of employment (year)
mean ± SD
Computer use
(hours/day)
mean ± SD
Complaints (%)
NoneGeneralEye and visionNeck and shoulderUpper extremityLower extremityTrunk

King Abdulaziz University computer users
Data entry 2237.529.45.67.031410127110
(6.6)(9.4)(7.8)(2.1)(13.6)(63.4)(45.5)(54.5)(31.8)(4.5)(45.5)
Typist 2336.933.89.87.131714148310
(8.2)(9.3)(6.7)(3.0)(13.0)(73.9)(60.9)(60.9)(34.8)(13.0)(43.5)
Data acquisition 1835.433.58.66.01131283411
(6.3)(10.6)(7.3)(2.0)(5.6)(72.2)(66.7)(44.4)(16.7)(22.2)(61.1)
Communication task 837.028.44.16.63333203
(5.8)(5.9)(5.9)(5.5)(37.5)(37.5)(37.5)(37.5)(25.0)(0.0)(37.5)
Comprehensive 2936.830.05.44.841020134614
(9.2)(7.5)(6.0)(1.9)(13.8)(34.5)(69.0)(44.8)(13.8)(20.7)(48.3)

Saudi Airlines Ticket reservation operators
Data entry 5469.638.317.26.011282624141523
(12.0)(10.4)(11.1)(0.0)(20.4)(51.8)(48.1)(44.4)(25.9)(27.8)(42.6)
Data acquisition 2377.843.326.26.017343222
(15.8)(6.1)(7.1)(0.0)(73.9)(13.0)(17.4)(13.0)(8.7)(8.7)(8.7)
Communication task 2066.636.716.16.010998669
(9.6)(8.6)(10.8)(0.0)(50.0)(45.0)(45.0)(40.0)(30.0)(30.0)(45.0)
Comprehensive 382.039.019.36.03000000
(14.0)(1.7)(4.1)(0.0)(100)(0.0)(0.0)(0.0)(0.0)(0.0)(0.0)

Saudi Telecom Co. computer operators
Data entry 3383.431.78.97.272222186162
(12.7)(7.9)(8.1)(1.8)(21.2)(66.7)(66.7)(54.5)(18.2)(48.5)(6.1)
Data acquisition 985.130.05.39.30677331
(8.3)(3.7)(4.7)(2.0)(0.0)(66.7)(77.8)(77.8)(33.3)(33.3)(11.1)
Communication task 5379.428.25.46.9832282614309
(15.7)(7.0)(6.8)(2.1)(15.1)(60.4)(52.8)(49.1)(26.4)(56.6)(17.0)
Comprehensive 585.234.812.84.41320311
(17.1)(7.3)(9.3)(2.2)(20.0)(60.0)(40.0)(0.0)(60.0)(20.0)(20.0)


Work
satisfaction
Number of
operators
Ergonomic score
mean ± SD
Age (year)
mean ± SD
Duration of employment (year)
mean ± SD
Computer use
(hours/day)
mean ± SD
Complaints (%)
NoneGeneralEye and visionNeck and shoulderUpper extremityLower extremityTrunk

King Abdulaziz University computer users
Very satisfied 3938.033.78.56.481821217314
(6.5)(10.2)(8.2)(2.7)(20.5)(46.2)(53.8)(53.8)(17.9)(7.7)(35.9)
Satisfied 4336.630.15.36.0621221810724
(8.2)(9.2)(5.3)(2.2)(14.0)(48.8)(51.2)(41.9)(23.3)(16.3)(55.8)
Satisfaction to some extent 1033.534.48.46.21745513
(6.9)(11.2)(8.1)(2.4)(10.0)(70.0)(40.0)(50.0)(50.0)(10.0)(30.0)
Not satisfied 833.528.56.06.40585526
(9.7)(3.9)(5.0)(2.2)(0.0)(62.5)(100.0)(62.5)(62.5)(25.0)(75.0)

Saudi Airlines Ticket reservation operators
Very satisfied 3576.239.618.96.022777757
(14.4)(8.4)(11.5)(0.0)(62.9)(20.0)(20.0)(20.0)(20.0)(14.3)(20.0)
Satisfied 3766.838.919.46.01116181481117
(11.6)(10.5)(11.3)(0.0)(29.7)(43.2)(48.6)(37.8)(21.6)(29.7)(45.9)
Satisfaction to some extent 1474.037.817.66.04768233
(11.0)(8.0)(9.1)(0.0)(28.6)(50.0)(42.9)(57.1)(14.3)(21.4)(21.4)
Not satisfied 1468.640.819.36.041086547
(11.6)(7.6)(8.6)(0.0)(28.6)(71.4)(57.1)(42.9)(35.7)(28.6)(50.0)

Saudi Telecom Co. computer operators
Very satisfied 2982.130.17.27.561411167114
(16.6)(7.3)(7.2)(2.1)(20.9)(48.3)(37.9)(55.2)(24.1)(37.9)(13.8)
Satisfied 3184.131.07.56.952221158166
(11.0)(8.7)(7.4)(2.0)(16.1)(71.0)(67.7)(48.4)(25.8)(51.6)(19.4)
Satisfaction to some extent 2779.328.55.17.051718137142
(14.8)(5.6)(6.3)(2.2)(18.5)(63.0)(66.7)(48.1)(25.9)(51.9)(7.4)
Not satisfied 1378.429.07.37.001097491
(15.1)(6.2)(7.5)(2.2)(0.0)(76.9)(69.2)(53.8)(30.8)(69.2)(7.7)


ComplaintsNumber of
operators
Ergonomic score
mean ± SD
Age (year)
mean ± SD
Duration of employment (year)
mean ± SD
Computer use
(hours/day)
mean ± SD
Complaints (%)
NoneGeneralEye and vision

King Abdulaziz University computer users
None 5836.630.95.46.0122725
(7.5)(9.2)(5.6)(2.0)(20.7)(46.6)(43.1)
Short-sighted 3037.631.35.46.612025
(8.3)(8.8)(5.6)(3.2)(3.3)(66.7)(83.3)
Long-sighted 737.240.418.05.7133
(6.7)(11.4)(10.8)(2.0)(14.3)(42.9)(42.9)
Others 736.539.811.95.6125
(4.9)(13.7)(12.3)(2.1)(14.3)(28.6)(71.4)

Saudi Airlines Ticket reservation operators
None 7071.438.918.56.0411813
(13.0)(9.1)(10.9)(0.0)(58.6)(25.7)(18.6)
Short-sighted 2372.238.718.96.001719
(13.2)(10.6)(11.4)(0.0)(0.0)(73.9)(82.6)
Long-sighted 265.047.526.56.0022
(12.8)(0.7)(0.7)(0.0)(0.0)(100.0)(100.0)
Others 568.843.622.86.0035
(19.0)(4.8)(6.1)(0.0)(0.0)(60.0)(100.0)

Saudi Telecom Co. computer operators
None 5880.429.15.87.2132924
(14.9)(6.9)(6.0)(2.0)(22.4)(50.0)(41.4)
Short-sighted 2484.830.38.16.731920
(12.9)(6.2)(7.6)(2.1)(12.5)(79.2)(83.3)
Long-sighted 1180.030.56.67.2088
(13.5)(9.5)(8.4)(2.1)(0.0)(72.7)(72.7)
Others 786.032.710.07.4077
(14.6)(9.3)(10.3)(2.7)(0.0)(100.0)(100.0)


Complaints Number of
operators
Ergonomic score
mean ± SD
Age (year)
mean ± SD
Duration of employment (year)
mean ± SD
Computer use
(hours/day)
mean ± SD
Complaints (%)
NoneGeneralNeck and shoulderUpper extremityLower extremityTrunk

King Abdulaziz University computer users
None 5937.631.66.56.013242017620
(7.7)(9.0)(6.6)(2.4)(22.0)(40.7)(33.9)(28.8)(10.2)(33.9)
Neck 2236.029.76.35.9113219315
(7.3)(8.2)(6.6)(1.5)(4.5)(59.1)(95.5)(40.9)(13.6)(68.2)
Shoulder and arms 1137.229.57.26.4199827
(8.8)(8.8)(7.8)(1.5)(9.1)(81.8)(81.8)(72.7)(18.2)(63.6)
Lower trunk 1332.231.47.87.4011113312
(8.7)(8.5)(7.3)(3.6)(0.0)(84.6)(84.6)(23.1)(23.1)(92.3)
Thigh and leg 533.434.89.68.2042133
(7.0)(15.8)(9.0)(5.6)(0.0)(80.0)(40.0)(20.0)(60.0)(60.0)
Others 141.035.02.07.0010001
(0.0)(0.0)(0.0)(0.0)(0.0)(100.0)(0.0)(0.0)(0.0)(100.0)

Saudi Airlines Ticket reservation operators
None 6271.438.418.76.039118447
(13.6)(9.1)(11.2)(0.0)(62.9)(17.7)(12.9)(6.5)(6.5)(11.3)
Neck 2474.439.819.46.002421121116
(13.4)(8.9)(9.7)(0.0)(0.0)(100.0)(87.5)(50.0)(45.8)(66.7)
Shoulder and arms 1175.442.321.86.001011757
(10.4)(8.4)(10.0)(0.0)(0.0)(90.9)(100.0)(63.6)(45.5)(63.6)
Lower trunk 2370.641.722.46.011515121418
(13.6)(10.1)(10.4)(0.0)(4.3)(65.2)(65.2)(52.2)(60.9)(78.3)
Thigh and leg 873.440.219.06.0175656
(15.2)(7.7)(8.9)(0.0)(12.5)(87.5)(62.5)(75.0)(62.5)(75.0)
Others 178.045.020.06.0011011
(0.0)(0.0)(0.0)(0.0)(0.0)(100.0)(100.0)(0.0)(100.0)(100.0)

Saudi Telecom Co. computer operators
None 5581.129.46.47.31331247207
(14.5)(7.7)(6.9)(2.0)(23.6)(56.4)(43.6)(12.7)(36.4)(12.7)
Neck 1782.930.17.96.9016138123
(11.8)(5.8)(7.9)(1.5)(0.0)(94.1)(76.5)(47.1)(70.6)(17.6)
Shoulder and arms 484.030.07.56.5042010
(9.3)(4.6)(7.3)(1.0)(0.0)(100.0)(50.0)(0.0)(25.0)(0.0)
Lower trunk 1682.332.38.66.811076121
(15.1)(8.5)(8.4)(3.0)(6.3)(62.5)(43.8)(37.5)(75.0)(6.3)
Thigh and leg 484.527.24.67.5012331
(12.0)(3.9)(4.2)(1.9)(0.0)(25.0)(50.0)(75.0)(75.0)(25.0)
Others 472.027.73.06.3213221
(25.9)(3.5)(2.1)(2.8)(50.0)(25.0)(75.0)(50.0)(50.0)(25.0)

It is worth noting that the lowest eye and vision complaints occurred among the operators who had the lowest level of education (i.e., middle education), which might be interpreted by their relatively lower involvement in vision tasks than the operators having higher levels of education.

As related to the impact of type of work on the incidence of complaints, results in Table 14 show that the operators who were involved in communication tasks in KAU, and in data acquisition in SAUDIA, had the lowest general, eye and vision, neck and shoulder, lower extremities, and lower trunk complaints, as well as those involved in comprehensive activities among all the populations, meanwhile showing the highest freedom from all complaints. It may be noted that the numbers of operators involved in these activities (KAU communication tasks and SAUDIA and STC comprehensive tasks = 8, 3, and 5, resp.) were the lowest among all worker involved in other types of activities which might have some effect on the results.

Nevertheless, the work satisfaction showed clear impact on the incidence of health complaints among the examined computer users, where the percentages of those who were free from complaints got higher by the improvement of work satisfaction (Table 15); meanwhile, the lowest incidences of mostly all the complaints were the lowest among the very satisfied operators, particularly the SAUDIA and STC operators.

The history of previous ailments among computer users/operators, also, had some impact on the reported complaints among them, where the percentages of the present complaints among the subjects who had no previous ailments were less than among the other subjects reporting related ailments’ history (Tables 1618).


Score of workstationKAU computer usersSaudi Airlines Ticket reservation operatorsSaudi Telecom Co. computer operators
Operator sampleNo
general complaints
No
eye and vision
complaints
No
musculo-skeletal
complaints
Operator sampleNo
general complaints
No
eye and vision
complaints
No
musculo-skeletal
complaints
Operator sampleNo
general complaints
No
eye and vision
complaints
No
musculo-skeletal
complaints

<50 8331 3110
(37.5)(37.5)(12.5)(33.3)(33.3)(0.0)
50–59 10436 21111113 3222
(40) (30)(60)(52.4)(52.4)(61.9)(66.7)(66.7)(66.7)
60–69 15867 22131414 11333
(53.3)(40)(46.7)(59.1)(63.6)(63.6)(27.3)(27.3)(27.3)
70–79 26131513 35242318 2481312
(50)(57.7)(50)(68.6)(65.7)(51.4)(33.3)(54.2)(50)
80–89 25121010 8434 23111112
(48)(40)(40)(50)(37.5)(50)(47.8)(47.8)(52.2)
90–100 16959 148109 36121115
(56.3)(31.3)(56.3)(57.1)(71.4)(64.3)(33.3)(30.6)(41.7)
Total100100100

4. Conclusions

The average ergonomics score at STC was 81% which may be considered as a good level. However, and unexpectedly, the average ergonomics scores at KAU and SAUDIA were only 73.3% and 70.3%, respectively. It had been anticipated that the average ergonomics scores for the computer workstations existing in leading institutions like KAU and SAUDIA should be considerably higher.

Although the examined populations in KAU and STC were relatively young and, consequently, had relatively short employment work duration, were relatively highly educated, had relatively low smoking index and low history of ailments before employment, had some type of on-the-job and/or formal training, mostly use computer daily for <7 hours and continuously getting rest pauses, and were mostly satisfied at work, yet they had somewhat high incidences of general complaints (e.g., body fatigue, headache, and lack of concentration), vision complaints, and musculoskeletal complaints. However, within SAUDIA population, surprisingly, the highest health complaints were among the youngest operators, who also had the lowest duration of computer work, as well as among those who had on-the-job and/or formal training; meanwhile, no systematic effect of the workstations’ ergonomic scores on the incidence of the complaints was observed. These anomalies might be attributed to having some of the operators who developed complaints there left or changed their work.

Naturally, the operators who were satisfied by their work and those who were conducting comprehensive works (i.e., variable types of work) as well as those who had no, or inconsiderable, history of previous ailments had the least incidence of the health complaints.

Meanwhile, higher incidences of the complaints existed among the smoking operators and those who did not work continuously with computer, as well as those who rated themselves as fast operating.

In summary, the incidence of the various complaints had been demonstrated, generally, to increase by (a) the decrease in the ergonomics score of the workstations, (b) the progress of age and duration of employment, (c) the increase of smoking habit, (d) the continuous daily use of computer, (e) the lack of work satisfaction, and (f) the history of operators’ previous ailments. However, unexpectedly, no effect could be demonstrated of the operators’ formal training and the daily hours of computer use, on the incidences of the complaints.

It is anticipated that the incidences of the different complaints among the examined population increased by their progress in the duration of work. Therefore, it is recommended that rapid actions should be taken to improve the ergonomics of the computer workstations. The improvement of each workstation should be considered separately with reference to the evaluation checklist of its individual components.

Setting up training programs for computer operators to efficiently use their computers and optimize their posture and movements inside their computer workstations based on ergonomics principles is highly recommended. Also, motivation of workers to learn about computer work-related health disorders, their causes, etiology, preferable postures and movements, and the role of fitness exercise, and encouraging them to take rest pauses within their work shifts, all are recommended.

It is recommended to conduct preplacement examination for computers’ operators to exclude subjects with history of ailments that might be aggravated by computer use and to have available health baseline for the employed subjects as well as periodical medical examination (annually or each two years) to assure normal health background and to early discover any deviation from normality.

Finally, the study recommends extending the research to cover the sectors of computer and VDTs users, particularly those employed by small offices and medium-size enterprises where it is anticipated to have ergonomics poorly designed workstations. Also, particular interest may be forwarded to investigating the presently studied complaints among the female computer users in KSA.

Conflict of Interests

The author declares that there is no conflict of interests regarding the publication of this paper.

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