Minimizing the evidence-practice gap – a prospective cohort study incorporating balance training into pulmonary rehabilitation for individuals with chronic obstructive pulmonary disease

PR is delivered both as a six week in-patient program and a 12 week out-patient program at WPHC. Both programs deliver exercise training three times a week with each session lasting one hour. All patients are required to complete the Six-Minute Walk Test (6MWT) [ 27] and the Chronic Respiratory Questionnaire-Self-reported (CRQ-SR) [ 28] pre and post-PR. The 6MWT is an assessment of functional exercise capacity and the CRQ-SR is a questionnaire reporting on patients’ health status. These are the only outcome measures routinely recorded as part of the PR programs administered at WPHC. Data pertaining to these measurements was collected from clinical records.

To enable the pooling of results from inpatient and outpatient programs all patients underwent balance training three times a week for a period of six weeks for a targeted total of 18 sessions, each one lasting 30 min. This protocol is in keeping with the approach from a previous RCT [ 24].

Before the commencement of balance training, the researchers communicated with the ‘clinical service lead’ to arrange a time when all the HCPs responsible for the PR program could attend a one hour training session. The hour comprised of a power-point presentation given by one of the researchers (SH) regarding the benefits and practical applications of balance training and familiarization with the balance equipment (i.e. ramp, foam, bosu ball, step, obstacle course). For one week, two researchers (SH and JR) assisted the HCPs with the balance training sessions delivering guidance on; prescription, progression and providing practical demonstrations as requested.

The program content was informed by previous research [ 8, 22– 24] and conversations with the HCPs responsible for its delivery. Following the one hour education session, the HCPs decided how to best incorporate balance training into PR, through a series of meetings held independently of the researchers. The researcher’s (SH) role was to ensure the balance training was delivered in a way which was consistent with the evidence-base. For example, that the training was delivered thrice weekly, for 30 min per session and included all subcomponents of balance, especially biomechanics, transitions and gait, known to be the most impaired in individuals with COPD [ 22, 24]. Training logs, developed in collaboration between researchers and HCPs, contained three stages of balance training. Stage one contained basic balance exercises including; narrow stance with eyes closed, tandem stance, normal stance on foam, walking sideways. Stage two involved exercises such as; narrow stance throwing and catching a ball, narrow stance on foam with eyes closed, perturbations in narrow stance, sit on floor and stand up without a chair. Stage three was the most advanced requiring individuals to; stand on the bosu ball throwing and catching the ball, perform sit to stand with a medicine ball, respond to perturbations in tandem stance, complete a high level obstacle course. Decisions to adapt the PR program to accommodate balance training were made by the HCPs on a patient-by-patient basis.

The HCPs were provided with a copy of the patient’s brief Balance Evaluations and Systems Test (BEST) test scores [ 29]. Although the researchers conducted detailed balance assessments pre and post-PR to determine the program’s effectiveness, the brief BEST test was chosen rather than supplying the HCPs with the full BEST test because it is quick and easy to interpret. A detailed description of the full BEST test is provided under the heading; ‘balance outcome measures’. The brief BEST test includes just six items, one from each of the sub-systems for balance control (biomechanical, stability limits/verticality, anticipatory postural adjustments for postural transitions, reactive postural response strategies, weighting of sensory information for orientation and postural stability during gait), yet still enables balance training to be tailored according to the specific impaired balance systems identified in individuals patients [ 29]. Furthermore, HCPs were supplied with a copy of the patient’s brief BEST test scores upon completion of the program to provide individual feedback regarding the efficacy of the training.

For those individuals with COPD enrolled in the study, the first 30 min of each exercise session were dedicated to balance training. Patients would complete a variety of exercises each session which were informed by the results of the brief BEST test. Table  1 displays a sample balance training program. The HCPs recorded patients’ progress in their balance logs and advanced them through the three stages as they saw appropriate.

One therapist was required to supervise two patients during the balance training, although this varied depending on patients’ balance ability. Usually, a ratio of one therapist for three patients was adequate but on occasions for some exercises another person was required to supervise. Therefore, in a class size of 12, where six patients are doing balance training alongside PR and six patients are completing standard PR without balance training approximately three physiotherapists were required. Compared to standard PR without balance training one extra physiotherapist was required for 30 min three times a week, translating to an additional 0.05 full time equivalent position.

Following completion of the study, a focus group, guided by a topic guide and facilitated by a researcher (SH) experienced in qualitative research methods was held with the HCPs to explore their experiences and opinions regarding the feasibility of delivering balance training alongside PR to patients with COPD. The focus group was digitally recorded and transcribed verbatim. Data were analyzed thematically, with the support of NVivo software (v 9; QSR International, Melbourne, Australia). The initial coding for the transcript was conducted by one researcher (SH) and agreed with a second researcher (TA).

Age, gender, smoking history and pack years, use of walking aids and oxygen usage were recorded. Recent pulmonary function results (Forced Expiratory Volume in one second (FEV ₁) and Forced Expiratory Volume in one second/Forced Vital Capacity (FEV ₁/FVC)) and measurements of height and weight were retrieved from patients’ clinical records.

Patients’ attendance was recorded and adverse events monitored. To measure perceived change in balance status, a global balance transition item was used in which participants were asked to rate the amount of change they experienced in their balance over the training program on a five-point Likert scale (much better, a little better, no change, a little worse, much worse).

Individuals with COPD satisfaction with the training regimen was recorded by adapting an existing questionnaire used in a previous study on KT for single leg cycling in COPD [ 20]. The questionnaire was completed during patients post-assessment.

The balance outcome measures were completed before patients commenced PR and after the six week balance training program by two of three researchers (SH, TA and JR), all of whom had experience administrating the balance tests. The same rater conducted both the pre and post-tests for each individual patient.

The Berg Balance Scale (BBS) [ 30] consists of 14 items including activities such as: transfers, reaching, turning around and single legged stance. Items are graded on a scale ranging from zero (unable/unsafe) to four (independent/efficient/safe), with higher scores indicating greater balance control. The scale has demonstrated internal consistency, intra-rater and inter-rater reliability, content validity, construct validity and predictive validity for determining falls in older adults [ 31]. A change of 3.3 (or ≥4) has been suggested to represent the minimal detectable change (MDC) for elderly individuals with baseline BBS scores of 45–56 points. For individuals with lower baseline scores the MDC score is five to six points for community-dwelling older adults [ 32].

The Balance Evaluation Systems Test (BESTest) [ 33] evaluates six subsystems of balance control, including; biomechanical, stability limits/verticality, anticipatory postural adjustments for postural transitions, reactive postural response strategies, weighting of sensory information for orientation and postural stability during gait. The BESTest has demonstrated excellent inter-rater reliability and validity, it relates to patients’ balance confidence and it is useful for directing therapy by identifying subscales of balance which are more or less impaired.

The Activities-Specific Balance Confidence (ABC) scale [ 34] requires patients to indicate their confidence in performing 16 activities without losing their balance or becoming unsteady on an 11 point scale (0-100 %). Higher scores indicate greater balance confidence. The ABC scale has good test-re-test reliability and, internal consistency and predictive capacity for falls in older community-dwelling adults [ 31, 34]. A change of 13 % has been shown to reflect a MDC in balance confidence in community dwelling older adults.