Research Article A Revised Version of Diabetes Quality of Life Instrument Maintaining Domains for Satisfaction, Impact, and Worry Mohamad Adam Bujang , 1 Tassha Hilda Adnan , 2 Nur Khairul Bariyyah Mohd Hatta, 2 Mastura Ismail, 3 and Chien Joo Lim 1 1 Clinical Research Centre, Sarawak General Hospital, Ministry of Health Malaysia, Kuching, Malaysia 2 National Clinical Research Centre, Ministry of Health Malaysia, Kuala Lumpur, Malaysia 3 Health Clinic Seremban 2, Ministry of Health Malaysia, Seremban Negeri Sembilan, Malaysia Correspondence should be addressed to Mohamad Adam Bujang; adam@crc.gov.my Received 10 April 2018; Accepted 12 June 2018; Published 22 July 2018 Academic Editor: Eusebio Chiefari Copyright © 2018 Mohamad Adam Bujang et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Background. Diabetes quality of life (DQoL) instrument has been widely used to measure quality of life among diabetes patients. This study aimed to develop a revised version of DQoL instrument that incorporated issues of redundancies in the items and strengthen the basis of validity of the instrument. Methods. This was a cross-sectional study where diabetes patients were recruited from December 1, 2014, until end of March 2015 at a public health clinic in Peninsular Malaysia. A questionnaire that included patients’ information and DQoL instrument was distributed to patients. Item selection of DQoL instrument was conducted to screen and finalize the items based on issues of missing values and redundancy. Validity testing was conducted for the revised DQoL instrument based on exploratory factor analysis, confirmatory factor analysis, and Rasch analysis. Results. The pattern structure matrix yielded three domains similar to the original version with 18 items. The minimum factor loading from the structure matrix was 0.358. The item’s and person’s reliability was excellent with 0.92 and 0.84 for “satisfaction” domain, 0.98 and 0.60 for “impact” domain, and 0.99 and 0.57 for “worry” domain, respectively. Confirmatory factor analysis has dropped 5 items and the revised version of DQoL contained 13 items. Composite reliability of the revised version was computed for “satisfaction” domain (0.922; 95% CI: 0.909–0.936), “impact” domain (0.781; 95% CI: 0.745–0.818), and “worry” domain (0.794; 95% CI: 0.755–0.832). Conclusion. A revised version of DQoL that maintains the conceptualization of “satisfaction,” “impact,” and “worry” with 13 items was successfully developed. 1. Introduction Diabetes quality of life (DQoL) instrument was published in 1988 by the Diabetes Control and Complications Trial (DCCT) Research Group [1]. It was initially developed for a multicenter controlled trial to investigate the effect of two different diabetes treatment interventions on the incidence and progression of early vascular complications. The DQoL instrument which contained 46 items was used to measure health-related quality of life among diabetes patients based on three main domains, namely, “satisfaction,”“impact,” and “worry.” This instrument has been widely used in diabetes research for decades. As a questionnaire to measure quality of life for patients with diabetes mellitus, DQoL was reported to have very strong reliability and proven to be valid [1, 2]. Its reliability measures were evaluated based on test- retest reliability and internal consistency. Meanwhile, the basis of its validity was supported based on content and concurrent validity. Content validity was conducted among a group of experts while the concurrent validity was deter- mined by the support of other questionnaires such as Symp- tom Checklist-90-R (SCL), the Bradburn Affect Balance Scale (ABS), and the Psychosocial Adjustment to Illness Scale (PAIS). However, the development of DQoL instru- ment was not supported by construct validity, although statistical technique such as exploratory factor analysis is a common type of analysis which can be applied in ques- tionnaire development to construct domains for a latent variable [1]. Hindawi Journal of Diabetes Research Volume 2018, Article ID 5804687, 10 pages https://doi.org/10.1155/2018/5804687