Development of the Short-Form Yin Deficiency Scale Using Three Item Reduction Approaches

Table 6

Equidiscriminatory item-total correlation results by three percentile points.

25% cut-off points of the total scores (72 points)	Spearman correlation	50% cut-off points of the total scores (88 points)	Spearman correlation	75% cut-off points of the total scores (104 points)	Spearman correlation
Dry mouth^a	0.500	Weakness of the lower limbs^a	0.555	Night fever	0.531
Night fever^a	0.477	Low back pain	0.548	Afternoon fever	0.528
Low back pain^a	0.477	Afternoon flush^a	0.529	Night itch^a	0.505
Night hot soles^a	0.473	Night fever	0.523	Afternoon flush	0.503
Afternoon fever^a	0.467	Dull pain in the heel^a	0.523	Rough skin^a	0.491
Weakness of the lower limbs	0.450	Afternoon fever	0.521	Night hot soles	0.471
Sweating during sleep	0.446	Persistent cough^a	0.509	Weakness of the lower limbs	0.433
Residual urine	0.440	Residual urine^a	0.504	Residual urine	0.420
Bone steaming	0.437	Night hot soles	0.497	Dark yellow urine^a	0.409
Dull pain in the ankle or knee	0.436	Night itch	0.491	Dry mouth	0.380
Afternoon flush	0.435	Dull pain in the ankle or knee	0.457	Morning fatigue^a	0.371
Fatigue	0.424	Bone steaming	0.451	Hair loss^a	0.368
Dull pain in the heel	0.422	Morning fatigue	0.434	Dull pain in the heel	0.367
Afternoon cough	0.410	Sweating during sleep	0.432	Tinnitus	0.348
Night itch	0.384	Afternoon cough	0.430	Persistent cough	0.339
Dry and cracked heel	0.361	Night cough	0.428	Waking up due to night urination	0.325
Night cough	0.355	Fatigue	0.420	Afternoon cough	0.324
Dark yellow urine	0.338	Rough skin	0.420	Low back pain	0.323
Rough skin	0.331	Dark yellow urine	0.403	Night cough	0.322
Morning fatigue	0.328	Susceptibility to heat and cold	0.398	Dull pain in the ankle or knee	0.320
Persistent cough	0.326	Dry mouth	0.386	Sweating during sleep	0.318
Tinnitus	0.324	Hair loss	0.333	Susceptibility to heat and cold	0.313
Difficulty containing urine	0.303	Waking up due to night urination	0.322	Difficulty containing urine	0.310
Susceptibility to heat and cold	0.301	Difficulty containing urine	0.315	Frequent urination	0.307
Waking up due to night urination	0.293	Tinnitus	0.307	Fatigue	0.299
Hair loss	0.282	Frequent urination	0.294	Dry and cracked heel	0.296
Frequent urination	0.276	Dry and cracked heel	0.294	Bone steaming	0.276

^a15 items by summation of five top-ranked items among three percentile categories. All Spearman correlations had . Among the 15 items, “hair loss” had lowest EITC (0.368) and was finally removed.