Measurement properties of the short form 36 and health-related quality of life after intensive care in Morocco.

BACKGROUND

Intensive care patients have a health-related quality of life (HRQL) that differs from the normal population. The aim of this study was to evaluate the measurement properties of the Arabic version of the short form (SF)-36 and study the HRQL determinants in adult patients 3 months after discharge from an intensive care unit (ICU).

METHODS

A prospective cohort study after ICU discharge. At 3-month follow up, the SF-36 was administered in consultation or by telephone. Multitrait scaling analysis was used to confirm the hypothesized scale structure of the SF-36. Reliability was tested using (i) measuring internal consistency; and (ii) the test-retest reliability assessed using an intraclass correlation coefficient. Construct validity was tested by known-groups comparison using one-way analysis of variance (ANOVA) and analysis of covariance (ANCOVA).

RESULTS

A total of 145 survivors answered the SF-36. Item internal convergency was higher than 0.40 (0.77-0.99; 100% scaling success) and item discriminant validity was perfect (100% scaling success) except for physical functioning (81% scaling success). Cronbach's alpha exceeded 0.70 in all eight scales (0.84-0.99). Test-retest reliability conducted in 73 patients was above 0.80. Acceptability to patients appeared reasonable although considerable interview time was required to administer the SF-36. Construct validity was confirmed by lower scores being reported by women, older age and a high level of comorbidities groups. When adjusted for background data, ICU variables were not associated with the SF-36 scores.

CONCLUSIONS

The Arabic version of the SF-36 appears to be a robust tool in ICU. Background variables are the only significant determinants of HRQL 3 months after medical ICU discharge.