Margit Kooijman

28 Eighty-five LINH practices were included, providing a representative sample of Dutch general practices with regard to practice type (solo, dual, group or health centre), degree of urbanisation and region. Patients with ICPC L92 were also selected from the LIPZ database. Because this database is smaller, all patients who visited the physiotherapist between 2006 and 2010 (n = 1182) were selected. Forty-nine LIPZ practices were included and 116 physiotherapists delivered data, providing a representative sample of Dutch physiotherapy practices with regard to practice type (solo, dual, group), degree of urbanisation and region. This is also true for the selection of physiotherapists with regard to age and year of graduation but there are more male therapists (p = 0.01) that register for LIPZ and the number of direct patient-related working hours is higher (p = 0.05). Data collection In LINH, for every patient, a care episode was defined as the time between the first and last visit for L92 in 2008. Care episodes were constructed on the basis of EPICON, which is an algorithm that groups ICPC-coded contact records from electronic medical records in general practice into care episodes. This algorithm calculates care episodes for each year separately (Biermans et al., 2008). Prescriptions were registered in accordance with the Anatomical Therapeutic Chemical (ATC) classification system. Because not all prescriptions were linked to a diagnosis, a list was made of the most common prescriptions based on a group of patients with a known diagnosis of L92. For each of these prescriptions, the number of times they were prescribed during a shoulder-syndrome care episode was determined. Interventions were registered using CTG codes, which are standardised codes set by the Dutch healthcare authority for health care claims to health insurers. For the most common codes with a diagnosis of L92, the number of times they occurred during a care episode of shoulder syndrome was determined. Referrals were also registered and for the most common referrals with a diagnosis of L92, the number of times they occurred during a care episode of shoulder syndromes was established. Based on the information in the referral module, the total group of patients was split in two: patients referred for physiotherapy during the care episode versus patients who were not referred for physiotherapy. In LIPZ, a series of consecutive treatment sessions for shoulder syndromes was considered to be a care episode. For each care episode, the gender and age of the patient was registered. Also recorded were the duration of the complaint at intake, whether it was a recurrent com- plaint (when the complaint appeared after a symptom- free period of at least four weeks and at most two years) and the treatment goal(s). At the end of the treatment, therapists registered a maximum of three interventions that were applied in at least 50% of the treatment sessions. Besides these features of the treatment plan, the outcome was also registered (indication of the extent to which the treatment goals were met, according to the physiotherapist). Based on the mode of access, the total group of patients was split in two: patients referred by their GP versus patients who accessed physiotherapy directly.