Measuring professional competency of public health nurses: development of a scale and psychometric evaluation

Aims and objectives. To develop an instrument to measure public health nurse competencies in Taiwan and to test its psychometric properties. Background. Core competencies for public health nursing practice have been established in the USA and elsewhere but no equivalent studies have been undertaken in Taiwan. Design. Postal survey of self‐administered questionnaire to 1534 full‐time public health nurses (response rate 67·3%). Methods. The Public Health Nurse Professional Competency Scale was based on a literature review, the six key competencies identified by the Taiwan Nurses Association and the ‘typical’ tasks reported by nursing researchers. The scale comprised four domains and 38 items using a four‐point Likert scale. Validity and reliability of the scale were determined by a seven‐member professional panel and the content validity calculated for each domain. Discriminatory power and the item‐total correlation index were used to analyse and eliminate items. Convergent and discriminant validity were assessed and factor analysis to test the dimensions of the scale – stability was determined by interscale correlations, internal and test–retest reliability. Results. The mean age of respondents was 40·6 years (SD 8·54) with the majority holding an associate degree (67·0%). Participants had worked for an average of 11·7 years (SD 9·20) and 74·4% held a registered nurse license. The scale had strong content validity (Indices > 0·8) and good test–retest reliability (Cronbach’s α = 0·93–0·97). Nine items were excluded during factor analysis and three factors accounted for 46–82% of the total variance: (1) basic‐care, (2) community health management and (3) combined teaching and self‐development competencies. The scale had high discriminant validity. Conclusions. A Public Health Nurse Professional Competency Scale has been developed and shown to have good reliability and validity. Relevance to clinical practice. The scale can be used to assess the competencies of Public Health Nurses in Taiwan and improve the quality of clinical services provided.