Background: The aim of the study was to assess the use of the Nijmegen Clinical Screening Instrument (NCSI) and Short Form 36 (SF-36) in providing a detailed assessment of health status of Q-fever patients and to evaluate which subdomains within the NCSI and SF-36 measure unique aspects of health status.
Findings: Patients received a study questionnaire, which contained the NCSI and SF-36. Pearson correlation coefficients between subdomains of the instruments were calculated. The response rate was 94% (309 out of 330 eligible patients). Intercorrelations between subdomains of the NCSI were generally lower than of the SF-36. Four subdomains of the NCSI showed conceptual similarity (Pearson's r ≥ .70) with one or more subdomains of the SF-36 and vice versa. Subdomains that showed no conceptual similarity were NCSI Subjective Pulmonary Symptoms, Subjective Impairment, Dyspnoea Emotions and Satisfaction Relations, and SF-36 Social functioning, Bodily Pain, Role Physical and Role Emotional.
Conclusions: Our results show that either the NCSI or SF-36 can be used to measure health status in Q-fever patients. When the aim is to obtain a detailed overview of the patients' health, a combination of the two instruments, consisting of the complete NCSI and the four unique subdomains of the SF-36, is preferred.