INTRODUCTION: Disturbed sleep is a commonly reported symptom in FM. Both the Sleep Quality NRS and the MOS-Sleep have demonstrated positive psychometric properties in patients with FM; however, as generic sleep assessments, neither included FM patient input at concept elicitation nor item generation phases. This study evaluated the content validity of both measures in FM patients.
METHODS: Qualitative interviews were conducted in Raleigh, North Carolina and Detroit, Michigan with 20 adults who reported a physiciandiagnosis of FM. Sixteen participants were female, 13 were white, and the average age was 50 years. For consistency, the same two researchers conducted all interviews using a structured guide. Participants shared their general experiences with sleep in regard to FM and evaluated the measures in detail.
RESULTS: Participants responded positively to the Sleep Quality NRS as an overall assessment of their sleep. The majority of the participants (n = 14) stated they would not change the response numbering or anchor wording of the item. Participants also responded positively to the 24- hour recall of the Sleep Quality NRS. Similarly, participants found the MOS-Sleep appropriate and relevant, with 19 participants stating the measure captured all of their sleep-related symptoms. However, areas for potential modification were identified for the MOS-Sleep: one item combines the issues of awakening short of breath and awakening with a headache; most participants thought these should be split into two items. Participants also questioned the relevance of the snoring item, and half of the participants expressed a preference for a daily rather than a weekly recall.
CONCLUSION: While patients with FM were not part of the development of these generic sleep assessments, this study provides evidence of content validity for both measures, supporting their use in FM studies. Modifications to the MOS-Sleep may further improve the relevance of the measure to patients with FM.
