A new measure of exercise adherence: the ATEMPT (Adherence To Exercise for Musculoskeletal conditions)

Key points

1. 01ATEMPT is a 6-item self-report questionnaire scored 6-30, with a change of 4 or more indicating a meaningful shift beyond measurement error.
2. 02It was developed from six stakeholder-defined domains of exercise adherence and passed content validity checks with patients and physiotherapists.
3. 03Internal consistency was good (Cronbach's alpha 0.86, 95% CI 0.83 to 0.88) and test-retest reliability was good (ICC 0.84, 95% CI 0.78 to 0.88).
4. 04The smallest detectable change was 3.77 (95% CI 3.27 to 4.42), meaning a score shift of 4 or more is needed to detect real change.
5. 05Construct validity and responsiveness have not yet been established and require future longitudinal testing.

How it was conducted

Design

Cross-sectional questionnaire survey with a retest subsample for reliability testing

Participants

382 adults with musculoskeletal pain recommended exercise at 11 NHS physiotherapy clinics in the Midlands, England

Retest sample

112 participants who completed a retest questionnaire (mean interval 17 days, SD 10, range 5-63 days)

Primary outcome

Structural validity, internal consistency, test-retest reliability, and measurement error of the ATEMPT

Analysis

Confirmatory factor analysis (CFA) using Multidimensional Item Response Theory; Bayesian Information Criterion for model selection; ICC, SEM, and SDC for reliability

Setting

11 NHS physiotherapy clinics across 4 trusts in urban, suburban, and rural areas in England

What they found

• Confirmatory factor analysis: one-factor solution had the lowest BIC value (24258.93), indicating best model fit.
• 6-item ATEMPT: Cronbach's alpha 0.86 (95% CI 0.83 to 0.88); RMSEA 0.03, SRMR 0.04, TLI 1.0, CFI 1.0 (all within acceptable thresholds).
• Test-retest ICC for the 6-item version: 0.84 (95% CI 0.78 to 0.88), indicating good reliability.
• Smallest detectable change (SDC) for 6-item version: 3.77 (95% CI 3.27 to 4.42); SE of measurement: 2.67 (95% CI 2.31 to 3.16).
• Mean baseline score: 25.41 (SD 3.40); mean retest score: 25.27 (SD 3.39); mean change score: 0.14 (SD 4.63).
• No floor or ceiling effects observed; only 9 of 382 participants (2.4%) achieved the maximum possible score.
• 13 of 48 initial items were removed due to low response variation (SD less than 0.7); 35 items entered CFA.

Limitations

• Sampling bias is possible: patients willing to respond may have been more adherent to exercise, which could have affected which items were retained.
• Construct validity and responsiveness (including minimally important difference) have not yet been assessed and require future longitudinal studies.
• Adherence stability between test and retest could not be guaranteed, as no method exists to confirm participants' exercise behaviour was unchanged over 17 days.
• The sample was predominantly white (90.6%) and recruited from UK NHS clinics only, limiting generalisability to other ethnicities and healthcare settings.

Why it matters

For patients

If your physiotherapist uses ATEMPT, it can help track how consistently you are following your exercise plan and flag when extra support might be helpful.

For clinicians

ATEMPT provides a brief, validated 6-item tool to monitor exercise adherence during treatment; a score change of 4 or more signals a real shift worth investigating.

For readers

This study fills a recognised gap by producing the first psychometrically sound adherence measure built from patient and clinician input, though construct validity testing is still needed.