Development and testing of the Dutch Heart Failure Knowledge Scale

Background: Heart failure (HF) knowledge as well as compliance are considered to be underlying mechanisms of the effects of HF management programs. However, there are no valid and reliable measurement instruments available which measures knowledge of HF patients. Aim: To develop a reliable and valid instrument, which measures the knowledge, patients have on their disease and the HF-related health care regimen. Methods: The HF knowledge scale was developed in 3 phases; (1) concept analysis and first construction, (2) revision of items and (3) testing for validity and reliability. Results: The Dutch HF knowledge scale is a 15-item, self-administered questionnaire that covers items concerning HF knowledge in general, knowledge on HF treatment (including diet and fluid restriction) and HF symptoms and symptom recognition. Face validity as well as content and construct validity was tested in HF patients in 19 hospitals in the Netherlands. The scale was able to differentiate between HF patients with high and low level of HF knowledge. Cronbach's α of the knowledge scale in this population (n = 902) was .62. Conclusion: The instrument is a valid and reliable scale that can be used in research to gain insight in the effect of education and counselling of HF patients. After additional testing, the instrument seems to be a valid and reliable scale to be used in clinical practice to measure HF knowledge.