Pharmacists' influences on prescribing: validating a clinical pharmacy services survey in the Western Pacific Region

Hospital pharmacists around the world are becoming increasingly involved in promoting the responsible use of medicines through clinical pharmacy services. This is reflected in the Basel Statements developed by the International Pharmaceutical Federation Hospital Pharmacy Section, particularly the theme 'Influences on Prescribing.' Some countries, particularly in Asia, are currently establishing clinical pharmacy services and would benefit from identification of facilitators.

To validate a survey exploring clinical pharmacy services focusing on pharmacists' influences on prescribing, based on Basel Statements 28-31, and the factors that affect their implementation in the Western Pacific Region (WPR).

Content and face validity of the survey (BS28-31) was established. This resulted in the BS28-31 consisting of 20 questions, which included a Clinical Pharmacy Services Facilitators (CPSF) scale (25 items) to measure respondents' perceptions of facilitators of clinical pharmacy services. The BS28-31 was emailed to hospital pharmacy directors in the WPR. The survey was made available in English, Japanese, Chinese, Vietnamese, Lao, Khmer, French and Mongolian. Principal components and internal consistency analyses were conducted to assess the reliability and construct validity of the CPSF scale.

The final survey was sent to a total of 2525 hospital pharmacy directors in the WPR of which 726 were returned from 31 nations yielding a response rate of 29%. Two items in the scale were removed due to low communalities (0.22 and 0.16). The resulting 23 item scale produced a parsimonious two-factor solution, divided into internal (e.g. individual pharmacist traits and pharmacy departmental structure/resources) and environmental facilitators (e.g. government support, patient and physician expectations). This two factor solution explained 51.5% of the variance. In addition, the Cronbach's α for the internal and environmental subscales were 0.94 and 0.78 respectively.

The BS28-31 survey was found to be a reliable and valid instrument for assessing hospital pharmacy directors' perceptions of clinical pharmacy services regarding pharmacists' influences on prescribing and their facilitators in the WPR.