The Malay version of SF-36 health survey instrument: testing data quality, scaling assumptions, reliability and validity in post-coronary artery bypass grafting (CABG) surgery patients at the National Heart Institute (Institut Jantung Negara—IJN), Kuala Lumpur

Table 4 Malay SF36: Tests of scaling assumptions

Scale	No. of items per scale (k)	Item internal consistency			Item discriminant validity
Scale	No. of items per scale (k)	Range (correlation coefficients)^a	Comparison^b	Success rate (%)	Range (correlation coefficients)^c	Comparison^d	Success rate (%)
PF	10	0.49–0.83	10/10	100	0.00–0.40	70/70	100
RP	4	0.71–0.85	4/4	100	0.01–0.53	28/28	100
BP	2	0.91–0.94	2/2	100	0.02–0.46	14/14	100
GH	5	0.20–0.50	3/5	60	0.02–0.44	33/35	94.30
VT	4	0.44–0.56	4/4	100	0.02–0.42	28/28	100
SF	2	0.50–0.54	2/2	100	0.06–0.60	14/14	100
RE	3	0.64–0.87	3/3	100	0.01–0.55	21/21	100
MH	5	0.29–0.61	3/5	60	0.01–0.34	33/35	94.30

PF Physical Functioning, RP role limitations due to Physical Health, RE role limitations due to Emotional Problems, VT Vitality, MH Mental Health, SF Social Functioning, BP Bodily Pain, GH General Health
^aCorrelations between items and hypothesized scale, corrected for overlap
^bNumber of items out of k with correlation ≥ 0.40
^cCorrelations between items and other scales
^dNumber of items out of 7 × k where difference between the correlation of the item with its own scale and correlation with the other scales ≥ 2SE (= 0.0576)

ISSN: 1477-7525