Personalised Outcomes Forecasts of Supervised Exercise Therapy in Intermittent Claudication: An Application of Neighbours Based Prediction Methods with Routinely Collected Clinical Data

Evaluating the implementation of personalised outcomes forecasts to optimise supervised exercise therapy in patients with intermittent claudication in the Netherlands: a multimethods study

BACKGROUND

To support the optimisation of supervised exercise therapy (SET) in patients with intermittent claudication, we developed personalised outcomes forecasts (POFs), which visualise estimated walking distance and quality of life for individual patients. The POFs may enable healthcare professionals, such as physical and exercise therapists, to improve shared decision-making and patient outcomes.

OBJECTIVES

To assess differences in patient outcomes (functional walking distance, maximal walking distance and health-related quality of life) and the level of shared decision-making before and after the implementation of POFs in the conservative treatment of patients with intermittent claudication.

METHODS

An interrupted time series design was used to compare preimplementation and postimplementation differences on patient outcomes. Using routinely collected data, differences from baseline to 6 months were compared between patients before and patients after the implementation. To compare levels of shared decision-making, we conducted observations of initial consults within a sample of physical or exercise therapists both before and after the implementation. Audiorecords of observations were scored on shared decision-making using the OPTION-5 instrument.

RESULTS

Differences in improvements between patients with whom POFs were discussed (n=317) and patients before the implementation of POFs (n=721) did not reach statistical significance for both functional walking distance (experimental vs. control=+23%, p=0.11) and maximal walking distance (experimental vs. control=+21%, p=0.08). For health-related quality of life, the POFs-informed patients showed a statistically significant greater improvement of 4% (p=0.04). Increased levels of shared decision-making were observed in postimplementation consults (n=20) when compared with preimplementation consults (n=36), as the median OPTION-5 total score showed a statistically significant increase from 45 to 55 points (p=0.01).

CONCLUSIONS

Integrating POFs into daily practice of SET for patients with intermittent claudication could assist in improving health-related quality of life and enhancing patient involvement. Using POFs did not result in statistically significant different improvements between groups on walking distances.

TRIAL REGISTRATION NUMBER

NL8838.

Personalized Reference Values for the Two-Minute Walk Test: An Analysis of Cross-Sectional Data From the National Institutes of Health Toolbox Study

OBJECTIVES

To develop reference values for the Two-Minute Walk Test (TMWT) via 2 previously untested methods: (1) smooth age-based statistical models and (2) a neighbors-based approach accounting for age, sex, and height.

DESIGN

Cross-sectional observational study.

SETTING

National Institutes of Health Toolbox study sites across the United States.

PARTICIPANTS

A total of 1385 healthy, community dwelling adult participants (age 18-85 years) in the National Institutes of Health Toolbox study were included in this analysis.

INTERVENTION

None.

MAIN OUTCOME MEASURES

Reference values for TMWT were generated using 2 approaches: (1) Generalized Additive Models for Location Scale and Shape, wherein TMWT values were modeled as a smooth function of age, and (2) a semiparametric neighbors-based approach. The performance of references values was then adjudicated by examining precision (ie, the average interquartile or interdecile range of reference values), and coverage (ie, the proportion of realized values included within a given inter-percentile interval). Agreement between methods was examined by intraclass correlation coefficient.

RESULTS

Neighbors-based reference values demonstrated a smaller average interquartile range (149 ft; 95% confidence interval [CI], 146-152 ft), compared with age-based reference values (158 ft; 95% CI, 155-162 ft), but similar average interdecile range (neighbors-based: 369 ft; 95% CI, 360-377 ft; age-based: 374 ft; 95% CI, 366-383 ft). Coverage appeared accurate via both approaches. Agreement between approaches was high (intraclass correlation coefficient=0.96), although differences were apparent on a case-by-case basis.

CONCLUSIONS

Both age-based and neighbors-based reference values offer viable options for interpreting a person's TMWT performance. In this analysis, the neighbors-based approach (adjusting for height) yielded potentially clinically relevant differences in reference values for persons at extremes of height.

Impact of Personalized Outcomes Forecasts on Clinical Reasoning of Physical Therapists in Intermittent Claudication: A Vignette Study

OBJECTIVE

Guidelines recommend supervised exercise therapy and lifestyle counseling by a physical therapist as initial treatment for patients with intermittent claudication. However, guidelines provide only a crude estimate of the outcomes that therapists and patients might expect from treatment. The purpose of this study was to explore the impact of personalized outcomes forecasts (POFs) on the decision-making process of physical therapists and to learn lessons on facilitating the use of forecasts in daily practice.

METHODS

A vignette-based, think-aloud interview study design was used. The participants were physical therapists trained in treating patients with intermittent claudication. Vignettes described fictitious patients diagnosed with intermittent claudication and included POFs. A directed approach was used to code, organize, and describe the data. Transcripts were analyzed using a thematic approach.

RESULTS

Sixteen therapists participated in the study. Three themes were identified: (1) setting and contextualizing treatment expectations, (2) setting (shared) goals and (de)motivating the patient, and (3) establishing and monitoring the treatment plan. Therapists mentioned that POFs could be useful for setting expectations and realistic treatment goals, contextualizing expected treatment response, stimulating patients to achieve their goals, and deciding on treatment frequency and treatment timing. Therapists thought POFs would be of less use for changing treatment goals during follow-up visits or for establishing intensity or type of training.

CONCLUSION

To overcome challenges that may arise when adopting POFs in daily practice, adequate training of physical therapists should be conducted. Potential areas to address with training include statistical and data literacy as well as guidance on integrating POFs with existing treatment protocols.

IMPACT

The use of POFs by physical therapists might contribute to a more person-centered care approach. The insights provided by this study on the first use of POFs by physical therapists can serve as an example and lesson on how to optimally implement such supporting tools into daily practice.