The PREHAB-study: Randomized multiple-baseline single-case study to test preliminary effectiveness of preoperative exercise in high-risk patients waiting for total hip replacement.
Summary
Objectives: To evaluate effectiveness and to explore experiences of patients of preoperative functional exercise during waiting period for total hip replacement(THR). Furthermore, the aim was to determine feasibility of multiple-baseline single-case study design in this study population.
Design: Randomized non-concurrent multiple-baseline single-case design. During baseline- and intervention period, participants completed repeated-measures every other day.
Setting: Patients’ living environment.
Participants: One man en three woman waiting primary THR and classified as high-risk for delayed inpatient recovery of activities.
Interventions: Patients trained functional activities in patients’ living environment, supervised one time per week and independent every day according the Better in Better out-standard.
Primary outcome measure: To assess effectiveness of preoperative exercise in included participants, Timed up and Go test was performed as repeated-measure to determine functional mobility. Furthermore semi-structured interviews were performed.
Secondary outcome measures: To assess feasibility of the study design, number of drop-outs, number of missing values, participants’ satisfaction with repeated-measures, number of non-participants, the occurrence of stable preoperative measurement and quality of the data was determined.
Results: Visual analysis showed significant improvement in functional mobility during intervention phase in one participant. Randomization testing showed no intervention effect for functional mobility(p=0.63). All participants found it useful to exercise in their home environment; two participants experienced less problems in functioning in daily living. All participants completed preoperative exercise. Participants pointed out that repeated-measures were easy to perform in daily life. 3.3% of repeated-measures was missing. Of planned ≥20 repeated-measures, one participant achieved this goal(range 9-22). Preoperative period varied from 4-9 weeks. Repeated-measures showed large fluctuations and trends in baseline phase which continued throughout intervention phase.
Conclusions: No effect of preoperative functional exercise on functional mobility in included participants could be found. However, the used study design seems not feasible in this study population. Nevertheless, patients were all positive regarding preoperative exercise. The data obtained through this multiple-baseline have highlighted several recommendations. Taking these into account, we think the study design could be feasible for giving insight in preliminary effectiveness of preoperative functional exercise in included participants.