Which instrument is more suitable to assess health-related quality of life: Nottingham Health Profile or Short-Form-36?

BACKGROUND

Recent publications in rehabilitation research describe a new category of outcome measures, so-called patient-reported outcomes (PROs). This is an umbrella term for different degrees of subjective symptom intensity, treatment satisfaction and, particularly, health-related quality of life (HrQoL). Given the countless new developments in the field of HrQoL, it has become difficult to select the most appropriate or the best instrument for outcome-oriented studies. We evaluated and compared the two most frequently used questionnaires to assess HrQoL, namely the Nottingham Health Profile (NHP) and the MOS Short-Form-36 Health Survey (SF-36) with regard to their applicability in gerontology.

METHODS

A sample of active "elderly gymnasts" (mean age, 68 years) was compared with a "young" control group (mean age, 36 years). Both groups were asked to fill out the two questionnaires and enter on a visual analogue scale (VAS) their assessment of the suitability of each instrument for application in a scientific study.

RESULTS

While the control group generally favoured the SF-36 and rated this questionnaire significantly better than the NHP, the two survey instruments were given nearly the same rating by the elderly gymnasts. Younger experimental subjects particularly objected to the wording of the items (all of these were found to be negatively oriented) and the dichotomous response format of the NHP (it allows only yes-no answers in contrast to the SF-36 which offers several graded choices) while elderly patients considered this limited range of responses to be an advantage of the NHP.

CONCLUSIONS

The decision in favour of or against a survey instrument should always be made individually for each situation, based on the test criteria and the characteristics of the study population. In elderly patients with stronger symptoms, one may well decide in favour of the NHP despite its disadvantages (limited response format, floor effects, less frequent use of the questionnaire).