New Fibromyalgia Quality of Life Scale May Improve Clinical Management

New research has developed a Fibromyalgia Quality of Life Scale (FM-QoLS) specific to patients with fibromyalgia with high validity and reliability that can be used to address the multifaceted QoL challenges of these patients.1

“Although several standardized tools have been used to evaluate symptom severity, functionality, and disease impact in fibromyalgia (i.e., the Fibromyalgia Impact Questionnaire and its revised version, there is no specific standardized questionnaire or scale that directly assesses QoL in fibromyalgia.2 Instead, in studies, QoL is evaluated by widely-used tools such as the Medical Outcomes Study Short Form (SF)-36, SF-12, Quality of Life Scale (QOLS), EuroQol (EQ-5D), and the Nottingham Health Profile (NHP). Given the lack in the literature, the current study aimed to develop a fibromyalgia-specific QoL scale,” lead investigator Ilke Coskun Benlidayi, MD, Department of Physical Medicine and Rehabilitation, Faculty of Medicine, Cukurova University, Adana, Türkiye, and colleagues wrote.1

Benlidayi and colleagues developed the scale in four steps: (1) Issue collection, (2) Face validity and selection of the most relevant items, (3) Formation of the preliminary scale and pilot testing, and (4) Psychometric evaluation. For psychometric evaluation, the scale was administered to a sample of fibromyalgia patients.

The investigators used the Kaiser–Meyer–Olkin (KMO) test and Bartlett's Test of Sphericity to assess suitability for exploratory factor analysis (EFA); Cronbach's alpha, Guttman split-half test, and test–retest correlations to assess reliability; and Principal Axis Factoring to determine construct validity with exploratory factor analysis.

Benlidayi and colleagues tested the correlation of the scale with established measures of QoL, fibromyalgia impact, fatigue, sleep, and mood to assess convergent validity and examine floor and ceiling effects. They first developed an item list including 25 issues related to QoL in fibromyalgia. They removed 10 issues after assessing and rating the initial list through cognitive interviews. The investigators administered the remaining questions to 60 patients with fibromyalgia before finalizing the FM-QoLS to contain 14 items and 2 domains: symptomatology-functionality and psychosocial. (After inspection of inter-item correlations, Q15 was found highly correlated with Q12 [correlation coefficient, 0.920] and was removed from the scale.)

The scale exhibited moderate-strong correlations between most items, indicating that the scale has a homogeneous structure and measures the same construct. The FM-QoLS showed moderate-strong correlations with pain, anxiety, depression, sleep, fatigue, and established measures of QoL. Regarding the test–retest reliability of FM-QoLS items, the gamma values ranged from 0.923 to 0.995 (P <.001 for all).1

“In conclusion, FM-QoLS is a 14-item QoL scale that is specific to patients with fibromyalgia. The scale has two domains: the symptomatology-functionality domain and the psychosocial domain. It allows for a comprehensive evaluation of fibromyalgia-related deterioration in QoL, with high reliability and validity. Future research could further refine the tool by exploring its use in diverse populations, as well as its role in informing treatment decisions and tracking patient progress over time. Compared to existing generic QoL measures, the FM-QoLS offers a detailed, fibromyalgia-specific perspective, which could help physicians better address the multifaceted challenges faced by patients,” Benlidayi and colleagues concluded.1

REFERENCES

1. Coskun Benlidayi I, Ornek C, Sariyildiz A, Sertdemir Y. Development of a fibromyalgia-specific quality of life instrument: the Fibromyalgia Quality of Life Scale (FM-QoLS). Rheumatol Int. 2025;45(6):142. Published 2025 May 16. doi:10.1007/s00296-025-05895-3

2. Bennett RM, Friend R, Jones KD, Ward R, Han BK, Ross RL (2009) The revised fibromyalgia ımpact questionnaire (FIQR): validation and psychometric properties. Arthritis Res Ther 11(4):R120. 10.1186/ar2783