The Construct Validity of an Instrument for Measuring Type 2 Diabetes Self-Care Knowledge in Nigeria
Purpose: To develop an instrument (DSCKQ-30) for measuring type 2 diabetic patients’ knowledge of self-care practices.
Methods: A 30-item questionnaire (DSCKQ-30) consisting of close ended questions was developed for this study. DSCKQ-30 was self administered to a cross-section of randomly selected 400 ambulatory adult diabetic patients (≥ 18 years), who were attending endocrinology clinics at the hospitals included in this study. The sex distribution for female and male was 56.7 and 43.3% respectively. Factor analysis and item analysis were performed to test the construct validity and reliability of the instrument. Item performance was measured by item discrimination (item-to-total correlation) and percent correctness (%C).
Results: The response rate was 78.5%. Factor analysis identified three scales of knowledge of self-care management. Chronbach’s alpha of the 30 questionnaire items was found to be 0.89. The item-to-total correlation coefficients and ranges for component 1 - 3 were 0.36 (0.25 - 0.48), 0.28 (0.23 - 0.35), and 0.34 (0.23 - 0.41), respectively, with overall average of 0.33 (0.23 - 0.48). Items percent correctness (% C) ranged from 16.7 to 86.7 % with an overall average of 55.6 %. Item factor loadings averaged 0.62 for the total items; averages of the three scales ranged from 0.59 to 0.68.
Conclusion: The DSCKQ-30 provided a quantitative measure of patient's knowledge of self-care practices.
Keywords: Diabetes self-care knowledge, DSCKQ-30, Knowledge instrument, Nigeria.
Submission of a manuscript to this journal is a representation that the manuscript has not been published previously and is not under consideration for publication elsewhere.
All authors named in each manuscript would be required to sign a form (to be supplied by the Editor) so that they may retain their copyright in the article but to assign to us (the Publishers) and its licensees in perpetuity, in all forms, formats and media (whether known or created in the future) to (i) publish, reproduce, distribute, display and store the contribution, (ii) translate the contribution into other languages, create adaptations, reprints, include within collections and create summaries, extracts and/or abstracts of the contribution, (iii) create any other derivative works(s) based on the contribution, (iv) to exploit all subsidiary rights in the contribution, (v) the inclusion of electronic links from the contribution to third party material where-ever it may be located, and (vi) license any thrid party to do any or all of the above.