Informed consent was obtained from each student and participation was voluntary (ethical approval EK 178/09). Recruitment of students was achieved via flyers posted on bulletin boards, as well as by e-mail. Participants were assured that all data collected would remain anonymous and confidential and performance would bear no impact on later evaluations or other assessments. A randomised study (RCT) was completed that was able to measure both the quantitative and qualitative parameters.
Six separate cohorts of medical students (2007–2010) were enrolled in the study (n = 304). Students were representative of the normal student population as a whole. All students included in the study denied any previous experience with SM therapy as well as any previous didactic or pedagogical training in a preliminary questionnaire. From this group, 12 willing students were chosen at random to serve as student-teachers (ST). The remainder of the students (n = 292) were then randomly assigned to a PAL group (PG) or a Staff group (SG). The SG was taught SM performances by two experienced physicians (both male orthopaedic surgeons), possessing at least 7 years of SM experience.
The ST were representative of the general student population. Each was given a 90-min introduction to the diagnostic and practical aspects of SM therapy by the two experienced orthopaedic surgeons in addition to 2 weeks of full-time preparation with the appropriate background literature [17
]. During this time and also during the period of the 8-week course, they had the opportunity to assist in SM manoeuvres in ambulant treatment everyday including autonomous practice of the SM techniques. Students volunteered as test objects in this context.
Students were divided into smaller teaching groups, each containing 6–12 students. Each treatment platform was shared by two students. The exposure took place in eight separate lessons (8 weeks), each lasting approximately 120 min. Traditionally, complex chiropractic techniques are taught beginning with theoretical aspects of SM (first 30 min), including bimanual motor learning principles. Topics included indications/contraindications, differences between mobilisation and manipulation, diagnostics, patient positioning, hand placement, specific anatomical contact, preload, thrust phases and the direction of force. Thereafter, students participated in a 90-min practical session in which they were able to practice specific manipulative and diagnostic techniques of the whole spine, including the sacroiliac joint. Duration and content of the teaching sessions for SG and PG were absolutely comparable because of the existence of a predefined curriculum, as defined by the German Society for Manual Medicine (DGMM) (three manipulative techniques of the cervical spine, two of the thoracic and lumbar spine each, three of the sacroiliac joint).
A multiple-choice questionnaire (MCQ: 20 questions, maximal 10 points) and an objective structured clinical examination (OSCE) were used to assess the learning effect at the end of the 8-week course. The final practical examination included a realistic patient scenario where fellow students played the part of the patient. The manipulative skills (positioning of the volunteer, hand placement, specific anatomical contact, preload, thrust phases and direction/level of force) were rated by using a school grading system (1 = excellent, 6 = fail), while students could achieve an OSCE score between zero and six for their palpatory diagnostic competencies assessing the functional musculoskeletal disturbances in the patient scenario. The students were separately evaluated (grades) by three external objective graders (all male orthopaedic surgeons, average determination) who were blinded as to which group the medical student was in, using a standardised rubric for manipulative skills (according to the standardised phases of manipulation technique). Points for diagnostic competencies (0–6 points) were awarded according to the number of correctly demonstrated steps to diagnose joint dysfunction in the cervical spine (soft tissue irritation, segmental mobility check, functional behaviour of segmental irritation) and focusing on the sacroiliac joint (including sacroiliac tests; Table ).
OSCE tasks including diagnostic and manipulative competencies
Reciprocally, each student assessed the quality of teaching they received using items rated on a 5-point Likert scale (5 = agree, 1 = disagree). Of primary interest was teacher competency, subjective evaluation of personal confidence in the newly learnt skills and the evaluation of the PAL system with respect to SM therapy. The knowledge transfer was again rated using the school grading system (1 = excellent, 6 = fail).
Analysis was performed using SPSS™ 17.0 (SPSS Inc., Chicago, IL, USA). In the cases where a normal distribution was present (MCQ, OSCE), a student t test was carried out; otherwise (assessment by Likert scale), non-parametric test methods such as the Mann–Whitney Wilcoxon test were used.