Introduction
Supplementary prescribing (SP) by pharmacists has recently been implemented into UK practice with the first prescribers registering with the Royal Pharmaceutical Society of Great Britain (RPSGB) in January 2004. This research aimed to determine the early experiences of all RPSGB registered prescribers.

Method
Subjects were all supplementary prescribers registered with the RPSGB (n=518). A self-completion questionnaire, consisting of closed and open questions and attitudinal items on 5-point Likert scales, explored course satisfaction, prescribing actions, benefits and challenges. Demographic data were also collected. After piloting (n=30), the questionnaire was mailed to the remainder (n=488) in June 2005. Non-respondents were sent three reminders at 2-weekly intervals. Test-retest reliability of the attitudinal items was assessed using Kendall's tau-b (n=14/17 of the pilot) and internal consistency of items on course satisfaction assessed using Cronbach's alpha (n=401). Predictors of starting to practise SP were identified using chi-square/Mann-Whitney U test and significant variables (p<0.05) tested using binomial logistic regression.

Results
The response rate was 82.2%. The 'learning in practice' focused on conditions including: cardiovascular (166 (41.4%)); respiratory (54 (13.5%)); endocrine (44 (11%)); central nervous system (36 (9%)); malignant disease (20 (5%)); and multiple conditions (34 (16.5%)). The median 'course satisfaction score' was 10 (range 3-15, 3 lowest to 15 highest) and had high internal consistency (? = 0.85) and test-retest reliability (Kendall's tau-b = 0.86).
195 (48.6%) [95% CI 43.8-53.5] were practising SP and 154 (79%) [72.7-84.1] had written at least one prescription, 116 (59.5%) [52.5-66.1] within 6 months of registration. The majority (135/154; 87.7%) [81.5-81.9] undertook a full medication review including drugs outwith the clinical management plan before prescribing. 90 (58.4%) of the first prescriptions were written in primary care medical practices and pharmacists were confident in their ability to prescribe (median 4, range 2-5, 1 lowest to 5 highest). First prescriptions covered a range of drug classes: ACE inhibitors/A-II receptor antagonists (11%); diuretics (9.1%); calcium channel blockers (5.2%); lipid regulating drugs (4.8%); antiplatelets (4.8%); anticoagulants (4.3%); bronchodilators (4.3%). Benefits of SP were thought to be: better patient management (59 (48.4%)); job satisfaction (22 (18%)) and better patient satisfaction (14 (11.5%)).
Independent factors predicting practising SP were: longer time since registering as SP [Odds Ratio 0.53; 95% CI 0.42-0.69; p<0.001]; confidence in prescribing ability [0.35; 0.23-0.54; p<0.001]; practising in a setting other than community pharmacy [3.06; 1.61-5.81; p=0.001]; training in cardiovascular conditions or multiple conditions during 'learning in practice' [0.51; 0.32-0.81; p=0.005]. These four factors explained 22.3% of the variance. Main reasons for not commencing SP were: no organisational recognition of SP (37 (18%)); lack of funding (33 (16%)); and non-availability of prescription pads (22 (10.7%)).

Discussion
Good progress has been made in implementing pharmacist SP, with a wide range of drugs and conditions being managed confidently. SP pharmacists need support in terms of infrastructure and integration into the healthcare team. This requires urgent action, especially now that pharmacist independent prescribing is on the horizon.1 Further research on the perspectives of other health professionals and patients with focus on outcomes is warranted.