Validity and reliability of the Finnish Motivation for Physical Activity (RM4-FM) questionnaire
Abstract Background There is a lack of properly validated instruments measuring motivation for physical activity in the Finnish language. The study aimed to translate the Motivation for Physical Activity (RM4-FM) instrument into Finnish and examine its psychometric properties in a sample of healthy, older Finnish adults. Methods The RM4-FM was translated and linguistically validated adhering to published guidelines. The sample consisted of 102 65–75-year old participants, who completed the RM4-FM, the Physical Activity Acceptance Questionnaire (PAAQ) and sociodemographic characteristics questionnaires electronically. The RM4-FM was re-administered one month after the initial assessment. Results RM4-FM translated well into Finnish. The motivation dimension scores were skewed towards high internal and low external motivation. A floor effect was confirmed in the External regulation dimension and a ceiling effect was confirmed in the Identified regulation dimension. Confirmatory factor analysis indicated inadequacy of the four-dimension model. Separate assessment of each of the four motivation dimensions with Exploratory factor analysis showed unidimensionality for all dimensions. Exploratory factor analysis provided a best-fit model of three factors (influence of other people, intention of well-being and emotional aspect of motivation). Re-administration of the instruments showed good test-retest reliability in all motivation dimensions. Female gender, higher education and higher PAAQ score were associated to higher internal motivation and lower external motivation scores. Conclusions The Finnish version of the RM4-FM instrument provides valid and reliable scores in assessing motivation for physical activity in a sample of healthy, older Finnish adults. The score distributions suggested shortages in the scale when evaluating internally motivated subjects. The three-factor model of the RM4-FM provided more favorable structural validity compared to the original version. This work may aid in future translations into other languages and uses of the questionnaire.