The Yale–Brown Obsessive–Compulsive Scale (YBOCS) and Compulsion Checklist (CC) were compared with one another and with five other measures to assess their place in measuring the outcome of obsessive–compulsive disorder (OCD).

Data came from a randomised trial of 46 patients with OCD who completed eight weeks of treatment by exposure and response prevention. Using a structured modelling analysis, the YBOCS and the CC were compared with a latent factor derived from five other variables (Target Rituals, Target Obsession, Clinical Global Impression, Avoidance, Disability) of baseline severity and change after treatment, and also directly with those variables.

Both the YBOCS and the CC were accurate and sensitive measures of OCD. The YBOCS related slightly more than did the CC to the latent factor and to Disability directly. The YBOCS related slightly more to Disability than it did to other measures. Inter-assessor and self v. assessor reliability was high.

The 10-item YBOCS plus the 4-item Disability scale are a simple and efficient way to measure important aspects of OCD in clinical practice.

A comparison of the performance of the 5-item mental health dimension of SF–36 (MHI–5) with that of the 12-item General Health Questionnaire (GHQ–12) in a defined, non-patient population, using standard statistical tests.

A postal survey of 3000 patients aged 16–64 years was conducted. Patients were randomly selected from the practice lists of two general practices chosen to represent populations with different socio-economic characteristics.

Considerable evidence was found for the internal consistency of both instruments (Cronbach's α 0.91 and 0.84 for GHQ–12 and the MHI–5 respectively) and for their construct validity in terms of distinguishing between groups with measured health differences. Both instruments showed a significant difference in the mean scores for men and women. In contrast to the GHQ–12, no correlation was found between age and score for the MHI–5. Both instruments were equally sensitive to socio-economic characteristics and to levels of social support The scores on the two instruments were highly correlated (Spearman rank correlation – 0.73).

The MHI–5 has comparable psychometric performance to the GHQ–12, and can be used to measure and compare mental health in defined populations. Operational advantages of the MHI–5 over the GHQ–12 are that it is in the public domain, is part of a general health measure (SF–36) and is shorter.

The aim of this study was to investigate the validity of the Arabic versions of the GHQ–30 and GHQ–12 in a sample of primary health care (PHC) patients in Al Ain, United Arab Emirates.

A randomly selected sample (n=157) of patients attending a PHC centre in Al Ain was screened using the Arabic version of the GHQ–30, the first 12 items of which constitute the GHQ–12. Then a standardised clinical interview using the Clinical Interview Schedule (CIS) was conducted with all screened patients. The receiver operating characteristic analyses of the Arabic versions of both GHQ–30 and GHQ–12 were compared and their correlation coefficients with the weighted total score of the CIS and the overall severity rate were estimated. Discriminant functional analysis was also performed to assess the discriminatory powers of both the GHQ–30 and GHQ–12.

Using the simple Likert scoring method, the best cut-off point of the GHQ–30, that balances between sensitivity and specificity, was 31/32 with a sensitivity of 0.83 and specificity of 0.83, and that of the GHQ–12 was 12/13 with a sensitivity of 0.83 and specificity 0.80. The total discriminatory powers of the GHQ–30 and GHQ–12 were approximately 93 and 86%, respectively. Both versions of the GHQ were found to have a significant concurrent validity.

The Arabic versions of both GHQ–30 and GHQ–12 are valid psychiatric screening instruments, with almost similar performance, for Arabic-speaking PHC patients.