An Audit of Diabetes Dependent Quality of Life (ADDQoL) for Portugal: exploring validity and reliability

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Filipa A. Costa
Jose P. Guerreiro
Catherine Duggan


Diabetes, Quality of life, Validation studies, Community pharmacy services, Questionnaires, Portugal


Objective: This paper describes the processes involved to ensure a diabetes-specific quality of life questionnaire [the “Audit of Diabetes Dependent Quality of Life” (ADDQoL)] retained the psychometric properties following cross-cultural adaptation from English to Portuguese.

Methods: One hundred patients were recruited through community pharmacies located in Lisbon through a cross-sectional study design. Patients were asked to respond to the questionnaire on one occasion in time. Data were subjected to factor analysis, and internal consistency and discriminatory power analyses were undertaken.

Results: In the Portuguese sample, 17 items loaded into one factor, with factor loadings above 0.43. The item “worries about the future” loaded weekly into this factor but if removed its internal consistency estimate increased very slightly (Cronbach’s alpha=0.89 to 0.90). A greater negative impact of diabetes on 16 of the 18 quality of life domains was detected for insulin-treated patients, together with a greater negative impact on 14 of the 18 quality of life domains for patients with diabetic complications. The domain “freedom to eat” revealed the greatest negative impact in all patient subgroups, as described in its original version, so the psychometric properties were retained.  Additionally, patients without diabetic complications reported a worse quality of life (greater negative impact) on the first overview item, present quality of life (Z=-2.25; p=0.024); whilst patients on insulin reported a greater negative impact of diabetes on their quality of life (Z=-1.94; p=0.053).

Conclusion: Generally, the Portuguese version for Portugal of the ADDQoL has shown to maintain its original psychometric properties, and could be recommended for use and further evaluation in subsequent studies.


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1. Costa S, Santos C, Silveira J. Providing Patient Care in Community Pharmacies in Portugal. Ann Pharmacother. (In press).

2. Anonymous. Atendimento a diabéticos evolui para nível superior. Farmácia Portuguesa 2003;146: 24-5.

3. Santos MR, Santos R, Costa S, Madeira A, Ferreira AP, Mendes Z et al. Improving Patient Outcomes and Professional Performance. Achieving Political Recognition. Pharmaceutical Care, beyond the pharmacy perspective. Conference Proceedings. 2005.

4. Roberts AS, Hopp T, Sorensen EW, Benrimoj SI, Chen TF, Herborg H et al. Understanding practice change in community pharmacy: a qualitative research instrument based on organisational theory. Pharm World Sci 2003; 25(5): 227-34.

5. Costa FA, Ferreira AP, Costa S, Santos R, Horta R, Fontes E et al. Contributos em Saúde para os Diabéticos. Avaliação do Programa de Cuidados Farmacêuticos: Diabetes. CEFAR, ANF. 2006.

6. Hepler CD, Strand LM. Opportunities and responsibilities in pharmaceutical care. Am J Hosp Pharm 1990; 47(3):533-43.

7. Areias ME, Kumar R, Barros H, Figueiredo E. Comparative incidence of depression in women and men, during pregnancy and after childbirth. Validation of the Edinburgh Postnatal Depression Scale in Portuguese mothers. Br J Psychiatry 1996; 169(1):30-5.

8. Coelho AM, Coelho R, Barros H, Rocha-Goncalves F, Reis-Lima MA. [Essential arterial hypertension: psychopathology, compliance, and quality of life]. Rev Port Cardiol 1997; 16(11):873-83.

9. Coelho R, Martins A, Barros H. Clinical profiles relating gender and depressive symptoms among adolescents ascertained by the Beck Depression Inventory II. Eur Psychiatry 2002; 17(4):222-6.

10. Coelho R, Ramos E, Prata J, Barros H. Psychosocial indexes and cardiovascular risk factors in a community sample. Psychother Psychosom 2000; 69(5):261-74.

11. Ferreira PL, Mendonça C, Newparth N, Mata P, Juniper EF, Mear I. Quality of life in asthma: cultural adaptation of the Juniper's AQLQ to Portuguese. Qual.Life Res 1998; 7[7]: 590.

12. Melchiors AC, Correr CJ, Rossignoli P, Pontarolo R, Fernandez-Llimos F. Humanistic-outcomes questionnaires in diabetes research and practice. Am J Health Syst Pharm 2005; 62(4): 354-5.

13. Melchiors AC, Correr CJ, Rossignoli P, Pontarolo R, Fernandez-Llimos F. Medidas de avaliação da qualidade de vida em diabetes. Parte II: instrumentos específicos. Seguimiento Farmacoterapéutico 2004; 2(2): 59-72.

14. Bradley C, Todd C, Gorton T, Symonds E, Martin A, Plowright R. The development of an individualized questionnaire measure of perceived impact of diabetes on quality of life: the ADDQoL. Qual Life Res 1999;8(1-2):79-91.

15. Bradley C, Speight J. Patient perceptions of diabetes and diabetes therapy: assessing quality of life. Diabetes Metab Res Rev 2002;18(Suppl 3):S64-S69.

16. Kline P. An Easy Guide to factor Analysis. London: Routledge, 1994.

17. Todd C, Bradley C. Evaluating the design and development of psychological scales. In: Bradley C, editor. Handbook of Psychology and Diabetes. Hove: Psychology Press; 1994: p.15-42.

18. Consumo de álcool na Europa. Eurotrials 2005;16:2-3.