Reliability and Validity of the Visual, Musculoskeletal, and Balance Complaints Questionnaire

Abstract

PurposeTo evaluate the reliability and validity of the 15-item Visual, Musculoskeletal, and Balance Complaints Questionnaire (VMB) for people with visual impairments, using confirmatory factor analysis (CFA) and with Rasch analysis for use as an outcome measure.MethodsTwo studies evaluated the VMB. In Study 1, VMB data were collected from 1249 out of 3063 individuals between 18 and 104 years old who were registered at a low vision center. CFA evaluated VMB factor structure and Rasch analysis evaluated VMB scale properties. In Study 2, a subsample of 52 individuals between 27 and 67 years old with visual impairments underwent further measurements. Visual clinical assessments, neck/scapular pain, and balance assessments were collected to evaluate the convergent validity of the VMB (i.e. the domain relationship with other, theoretically predicted measures).ResultsCFA supported the a priori three-factor structure of the VMB. The factor loadings of the items on their respective domains were all statistically significant. Rasch analysis indicated disordered categories and the original 10-point scale was subsequently replaced with a 5-point scale. Each VMB domain fitted the Rasch model, showing good metric properties, including unidimensionality (explained variances ≥66% and eigenvalues <1.9), person separation (1.86 to 2.29), reliability (0.87 to 0.94), item fit (infit MnSq’s >0.72 and outfit MnSq’s <1.47), targeting (0.30 to 0.50 logits), and insignificant differential item functioning (all DIFs but one <0.50 logits) from gender, age, and visual status. The three VMB domains correlated significantly with relevant visual, musculoskeletal, and balance assessments, demonstrating adequate convergent validity of the VMB.ConclusionsThe VMB is a simple, inexpensive, and quick yet reliable and valid way to screen and evaluate concurrent visual, musculoskeletal, and balance complaints, with contribution to epidemiological and intervention research and potential clinical implications for the field of health services and low vision rehabilitation.

Visual, musculoskeletal and balance symptoms in individuals with visual impairment

“…The VMB has good psychometric properties and good convergent validity . Construct validity, reliability and properties have been analysed by Confirmatory Factor Analysis and Rasch analysis . The internal consistency of the VMB in the present study was adequate as indicated by Cronbach's alpha values of 0.87 for VMB V, 0.95 for VMB M and 0.85 for VMB B. Thresholds are based on median levels of the total sample: VMB V ≥ 3.35, VMB M ≥ 1.75 and VMB B ≥ 1.90.…”

“…The VMB has good psychometric properties and good convergent validity . Construct validity, reliability and properties have been analysed by Confirmatory Factor Analysis and Rasch analysis .…”

Visual system disorders and musculoskeletal neck complaints: a systematic review and meta‐analysis

“…Several variations were observed in the measurement techniques used in different studies. Some authors used questionnaires to record the subjects’ symptoms with a self‐report system . Others analyzed neck musculature at the same time as the visual system was altered .…”

Visual, Musculoskeletal, and Balance Complaints in AMD: A Follow-Up Study

“…The VMB has adequate psychometric properties and convergent validity in people with visual impairments [32]. It consists of 15 questions, with five questions each in visual (VMB-V), musculoskeletal (VMB-M), and balance (VMB-B) domains.…”

“…The sum of the five scores in each domain is then calculated, with scores ranging from 0 to 50. The validated VMB-scale has been revised, with some minor changes [32]. The present study was performed with the use of the original VMB-scale [20], which was used at baseline and then at follow-up allowing for detection of individual changes using GEE.…”