A self-rated health score predicts severe disease and high mortality in patients with pulmonary TB.

Health-related quality of life (HRQoL) in patients with pulmonary TB may be predictive of disease outcome; however, HRQoL instruments are often complicated and unsuitable for use in low-resource settings. A single-item self-rated health (SRH) score may represent a simpler alternative which could be used in clinical decision-making. To evaluate internal and external validity of SRH and its correlation with TBscore/TBscoreII in a low-resource setting. We used data from our ongoing prospective TB cohort study in Guinea-Bissau. Cohen´s was used to assess internal validity, and receiver-operating characteristics and mortality statistics to assess external validity. Correlation between SRH and TBscore/TBscoreII was estimated using linear regression. SRH showed satisfactory internal validity and ability to discriminate between fatal cases at high and low scores, although not at middling scores. SRH and TBscore/TBscoreII correlated well at each examination but changes in scores did not, which may be due to ceiling/floor effects and a lag between disease severity and HRQoL. SRH shows potential as a quick and simple method to identify patients in need of intensified follow-up during treatment provision. More research is needed to assess its generalisability beyond our setting and to develop models for clinical use of SRH.