Development and quality assessment of the psychometric properties of the Self-Efficacy in Lifestyle Counselling scale (SELC 20 + 20) using Rasch analysis.

BACKGROUND: Globally as well as in Sweden, diseases that are caused by unhealthy lifestyle habits are the most common causes of death and disability. Even though there are guidelines that oblige all health-care professionals to counsel patients about lifestyle, studies have shown that it is not prioritized within healthcare. One reason for this among nurses has been shown to be lack of confidence in knowledge and counselling skills. This study aimed to develop, and quality assess the psychometric properties of an instrument to measure self-efficacy in lifestyle counselling. METHODS: An instrument inspired by an American instrument, following Bandura's recommendations for development of self-efficacy measures, was developed according to Swedish national guidelines for disease-prevention. The instrument was revised after cognitive interviews with nursing students, university teachers within health sciences, and clinical experts, then administrated to 310 nursing students at different levels in their education. The instrument was tested with Rasch Measurement Theory, with focus on dimensionality, local dependency, targeting, reliability, response category functioning, Rasch model fit, and differential item functioning by age, gender, educational level and previous health care education. RESULTS: The development of the instrument resulted in 20 + 20 items, 20 items about self-efficacy in knowledge, and 20 items about self-efficacy in ability to counsel persons about their lifestyle. The analyses showed that knowledge and ability are two different, but related, constructs, where ability is more demanding than knowledge. The findings provide support (considering dimensionality and local dependency) for that all 20 items within the knowledge construct as well as the 20 items within the ability construct can be summed, achieving two separate but related total scores, where knowledge (reliability 0.81) is a prerequisite for ability (reliability 0.84). Items represented lower self-efficacy than reported by the respondents. Response categories functioned as expected, Rasch model fit was acceptable, and there was no differential item functioning. CONCLUSIONS: The SELC 20 + 20 was found to be easy to understand with an acceptable respondent burden and the instrument showed good measurement properties.

The Swedish translation and cross-cultural adaptation of the Functional Assessment of Chronic Illness Therapy - Cervical Dysplasia (FACIT-CD): linguistic validity and reliability of the Swedish version.

BACKGROUND: Cervical dysplasia is a precancerous condition, which has been shown to create anxiety in women. To be able to investigate these women's health-related quality of life, a disease-specific instrument is required. There does not seem to be a Swedish version of an instrument to screen for this specific disease. Therefore, this study aims to translate and cross-culturally adapt the Functional Assessment of Chronic Illness Therapy - Cervical Dysplasia (FACIT-CD) into a Swedish context and evaluate its linguistic validity and reliability. METHODS: The Functional Assessment of Chronic Illness Therapy (FACIT) translation methodology was used, which consists of several steps including pilot testing of the FACIT-CD instrument through cognitive debriefing interviews. Ten women diagnosed with cervical dysplasia participated in the cognitive debriefing interviews. The internal consistency reliability of the Swedish FACIT-CD was estimated by Cronbach's alpha coefficient. Homogeneity of the items was evaluated by corrected item-total correlations. The sample consists of 34 women who were diagnosed with cervical dysplasia. RESULTS: The translation and cross-cultural adaptation went smoothly without any problems for the majority of the items. The cognitive debriefing interviews indicated that the Swedish FACIT-CD consists of relevant items, is easy to understand and complete, and has unambiguous and comprehensive response categories. The translation and cross-cultural adaptation resulted in a Swedish FACIT-CD, which is conceptually and semantically equivalent to the English version and linguistically valid. The total scale of the Swedish FACIT-CD exhibited good internal consistency reliability with a Cronbach's alpha coefficient of 0.84, and all of the subscales exhibited acceptable value between 0.71 and 0.81 except the Relationships subscale, which had a value of 0.67. Finally, all but four items exceeded the acceptable level for the corrected item-total correlations of ≥ 0.20. CONCLUSIONS: The Swedish FACIT-CD is conceptually and semantically equivalent to the English version and linguistically valid; further, it exhibits good internal consistency reliability.