Data Analysis
Data preparation and calculation of descriptive statistics were performed using SPSS 27 (IBM Corp. Released 2020. IBM SPSS Statistics for Windows, Version 27.0, Armonk, NY) and R (R foundation, Vienna, Austria). Subsequent analyses were performed using R. For a longitudinal analysis of the data, at least 2 EXAS scores are required. The first EXAS score can be calculated after treatment session 2, based on patient adherence to HBE recommendations from the physical therapist given during the first session. Similarly, the second EXAS score can be calculated after the third treatment and so on. Therefore, data from patients with fewer than 2 EXAS scores were excluded. Missing values analyses were performed to evaluate if observed variables were correlated with variables with missing data. Relationships between baseline variables and missingness of adherence variables were found; therefore, further analyses of the data were performed by assuming data were missing at random. Multivariate imputation by chained equations was used to impute missing data in R using the mice package.To assess the presence of subgroups of patients with distinct trajectories of adherence, LCGA was performed using the lcmm package in R.