Psychometric properties of the World Health Organization Quality of Life instrument (WHOQoL-BREF) in alcoholic males: A pilot study

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1 Qual Life Res (2005) 14: Ó Springer 2005 Psychometric properties of the World Health Organization Quality of Life instrument (WHOQoL-BREF) in alcoholic males: A pilot study A.F. Barros da Silva Lima 1, M. Fleck 1, F. Pechansky 1, R. de Boni 1 & P. Sukop 2 1 Department of Psychiatry and Legal Medicine, Federal University of Rio Grande do Sul, Brazil; ( afbslima@terra.com.br); 2 Hospital de Clı nicas of Porto Alegre, Brazil Accepted in revised form 25 March 2004 Abstract Objective: To evaluate criterion convergent and discriminant validity of the World Health Organization Instrument (WHOQoL-BREF) in evaluating quality of life and to verify its convergent validity with the Medical Outcomes study Short-forms (SF-36) and the Symptom Check List (SCL-90) instruments in male alcohol dependent patients who seek treatment at two Brazilian treatment centers. Methods: A crosssectional study was performed, in which cases were divided in to two groups according to the severity of alcohol dependence, ascertained by the Short Form Alcohol Dependence Data scale (SADD). Results: The sample was comprised of 36 males, and 63.9% had severe dependence. Subjects with low/moderate dependence showed higher scores in all domains of the WHOQoL-BREF and in nearly all domains of the SF-36. Criterion validity and internal consistency in the WHOQoL-BREF were satisfactory. With regard to convergent validity between the WHOQoL-BREF and SF-36, most correlation coefficients were significant. Conclusions: The WHOQoL instrument proved to be satisfactory for evaluating quality of life in this sample. Key words: Alcohol dependence, Quality of life, SF-36, WHOQoL-BREF Introduction Alcoholism is a prevalent disease of high social cost in Brazil, there are few prevalence studies, which point to rates of alcoholism between 3 and 12%, with a peak between 30 and 49 years of age [1 8]. In the U.S., the Epidemiological Catchment Area National Study showed a lifetime prevalence of alcoholism that ranged between 3 and 16% [9]. One of the traditional methods of evaluating alcoholism treatment outcomes to observe changes in the frequency and/or quantity of alcohol use. Longabaugh et al. and Metzger et al. stress the difficulty in establishing a cause and effect relationship between alcohol consumption and their effects in many aspects of life [10, 11]. Thus, the quality of life measure is potentially useful in the evaluation of alcoholism. Being a multidimensional construct, quality of life results in a broader view of the patient s health status, rather than simply the persistence or absence of symptoms or a restricted parameters of alcohol consumption and/ or abstinence [12 15]. There are not many studies in the literature concerned with quality of life in alcoholics. The association between quality of life and alcoholism still seems to be a controversial issue. Pattience et al. [16] and Volk et al. [13] note that quality of life appears to be more associated with use patterns (abusive or dependent) rather than with frequency or quantity consumed [13, 16]. The objective of this study was to evaluate the criterion and discriminant validity of the World Health Organization Quality of Life Instrument (WHOQoL-BREF) and verify its convergent validity with the Medical OutcomeS Study Short Form (SF-36) and Symptom Check List (SCL-90) instruments.

2 474 Method A cross-sectional study was developed. The sample was comprised of 36 male subjects, with ages ranging from 18 to 65 years. The selection process was performed in two ways: trough advertisements placed in major local newspapers, inviting subjects for an evaluation of their alcohol consumption and its consequence in their lives, and also through referrals for two alcoholism treatment centers in Porto Alegre, Brazil Inclusion criteria were as follows: (1) Alcohol dependence; (2) use of alcohol in the 30 days prior to the interview; (3) beginning of outpatient treatment (1st or 2nd visit), or under detoxification (7th 15th day of hospitalization). Exclusion criteria were: (1) subjects who had psychotic symptoms which made the completion of the instruments impossible; (2) organic brain syndrome; (3) co-morbidity with dependence or abuse of illicit drugs; 4) limiting clinical co-morbidity, unrelated to alcohol. The evaluation took from 60 to 90 min and consisted of a semi-structured interview for the diagnosis of alcohol dependence, based on DSM-IV criteria, applied by trained interviewers. All patients signed and informed consent form. In the screening the patients were interviewed using the Mini-Mental State Examination [17] and Mini International Neuropsychiatric Interview (MINI) [18]. The following self-instruments were also used: Short-Form Alcohol Dependence Data (SADD): One of the many instruments used to evaluate the severity of alcohol dependence syndrome, according to the criteria of Edwards and Gross [19 22]. World Health Organization Instrument To Assess Quality of Life Bref(WHOQoL-BREF): This is a short version of the World Health Organization Quality of Life assessment instrument, the latter being composed of 100 questions (WHOQoL-100). This instrument was developed simultaneously in 15 international centers, and was validated in Brazilian Portuguese [23 25]. Medical Outcomes Study Short-Form (SF-36): A generic instrument to measure functional state and well-being, which is used in clinical practice and in population-based research. [26]. Symptom Check List-90: An instrument composed of 90 items that identify nine groups of psychological symptoms. It has a global score, as well as specific scores for each domain. Its validity is well documented [27]. Statistical analysis Comparison among the categorical variables was implemented by means of the Chi-square test and the T-test for independent samples. The Mann Whitney U-Wilcoxon Rank Sum test was used for variables that did not display a normal distribution. The Hopkins effect size was also used to compare quality of life scores among groups [28]. The internal consistency of the WHOQoL-BREF for facets, domains, domains+facets and questions was evaluated by the Cronbach reliability coefficient. Results The sample included 36 cases, divided in two groups according to the severity of dependence. The majority of subjects reported severe dependence, corresponding to 63.9% of the cases. Most subjects (61.1%) had completed middle school, which corresponds to at least 8 years of schooling and 63.9% had jobs or were self-employed. Regarding socioeconomic levels, 55% of subjects came from Classes C, D or E, representing a low socioeconomic status. Demographic characteristics are described further in Table 1. The internal consistency of the WHOQoL- BREF was evaluated through Cronbach reliability coefficient. The coefficient for facets, domains, domains+facets and questions ranged between 0.78 and 0.89, confirming the good internal consistency of the instrument. The quality of life domains, measured by the WHOQoL and SF-36 were compared in two groups separated according to the severity of their alcohol dependence. The general means of the WHOQoL varied from (SD ¼10.08) for the environment domain, to (SD ¼10.56) for the social domain. For SF-36 instrument, means ranged from (SD ¼41.52) for the role emotional domain to (SD ¼20.95) for the physical function domain. When each domain was analyzed between groups, it was observed that for most areas patients with low to moderate

3 475 Table 1. Demographic characteristics of the sample Characteristics Total N (%) Mild/Mod Dep. N (%) Severe Dep. N (%) p Clinical Setting 0.78 Outpatients 26 (72.2) 10 (77.0) 16 (69.6) Inpatients 10 (27.8) 3 (23.0) 7 (30.4) Age 0.19 mean (sp) 46 (8.34) (7.77) (8.51) Schooling 0.74 Elementary 22 (61.1) 7 (53.8) 15 (65.2) High school 11 (30.6) 5 (38.5) 6 (26.1) College 3 (8.3) 1 (7.7) 2 (8.7) Marital status 0.51 Married 20 (55.6) 7 (53.8) 13 (56.5) Separated/divorced/ 11 (30.6) 3 (23.1) 8 (34.8) widower Single 5 (13.9) 3 (23.1) 2 (8.7) Life situation 0.67 Alone 6 (16.7) 2 (15.4) 4 (17.4) Partner/children 19 (52.8) 6 (46.2) 13 (56.5) Other relatives 10 (27.8) 5 (38.5) 5 (21.7) Other 1 (2.8) 0 1 (4.3) Employment 0.70 Self-employed 23 (63.9) 9 (69.2) 14 (60.9) Under pension 1 (2.8) 0 1 (4.3) Unemployed 8 (22.2) 2 (15.4) 6 (26.1) Retired 4 (11.1) 2 (15.4) 2 (8.7) a Economic status A(highest) 2 (5.6) 2 (15.4) 0 B 14 (38.9) 7 (53.8) 7 (30.4) C 15 (41.7) 3 (23.1) 13 (52.5) D 4 (11.1) 1 (7.7) 3 (13) E(lowest) 1 (2.8) 0 1 (4.3) Chi-squared test for all variables, except economic status, where the Mann Whitney test was applied and age where mean was applied. a Classification of Socioeconomic Level: This is a classification system based on household consumer goods and the head of the family s schooling score. It was developed by the association of Brazilian Market Institutes. This system is divided in 5 classes (A, B, C, D and E), where A represents the class with higher socioeconomic level and E represents the lower class[30].this is the only variable with a stastically significant difference with p = dependence achieved better scores, showing a significant difference and moderate or large size effect in most domains. Scores of the different domains are described in Table 2. When the convergent validity between the WHOQoL-BREF and SF-36 was analyzed, most correlation coefficients were significant. The SF-36 domains were more associated with the WHO- QoL s physical and psychological domains, with mostly moderate correlations. Data are reported in Table 3. There was also an inverse correlation between WHOQoL-BREF domains and total scores of the SCL-90, showing highest correlations between the physical and psychological domains with Pearson Coefficient correlation ranged between )0.63 and Discussion Results of the present study show that the WHOQoL-BREF has discriminant validity upon separating groups of alcohol dependents of varying severity, measured by the SADD in a statistical and clinically significant manner. Moreover, it shows good internal consistency when measured by the Cronbach coefficient, as well as satisfactory convergent validity when compared to other quality of life (SF-36) and general psychopathology (SCL-90) instruments.

4 476 Table 2. Comparison of the Mean scores of quality of life for the domains of the WHOQOL and SF-36, according to severity of dependence Domain Mild/moderate N = 13 Severe N = 23 p a ES b Mean SD Mean SD WHOQOL Physical Psychological Social Environmental SF-36 Physical function Role physical Bodily pain General health Vitality Social function Role emotional Mental health a Student s T-test for independent samples. b ES effect size. Table 3. Correlation coefficient among different WHOQOL and SF-36 domains Physical domain Psychological domain Social domain Environment domain Physical function 0.43* 0.52* 0.39* 0.47* Role physical 0.36** 0.43* * Bodily pain 0.50* 0.41* 0.37** 0.14 General health 0.52* 0.54* 0.46* 0.21 Vitality 0.56* 0.55* Social function 0.60* 0.68* 0.45* 0.44* Role emotional 0.59* 0.66* 0.47* 0.42* Mental health 0.74* 0.78* 0.58* 0.62* * Significance level <0.01; ** significance level <0.05. An association between quality of life and severity of alcohol dependence was observed. Patients with higher severity perceived themselves as having a lower quality of life. It is important to mention that the major differences found between levels of dependence with the WHOQoL-BREF were in the psychological and social domains and in relation to the SF-36, social aspects, role emotional and mental health. This finding suggests that, in fact, the phychological and social aspects are the most significant ones in the assessment of quality of life of alcohol dependents of different severities. This study, however, had some limitations. First, the sample size was small, limiting the possibility of stratified analyses. This was partly due to the extreme difficulty to find pure alcoholics alcohol dependent clients with no concomitant drug abuse or psychiatry comorbidity for this study. Furthermore, some findings of null statistical meaning may be derived from type II errors, such as in relation to certain domains of the SF-36 instrument ( Physical function and Role physical ).Second, as our sample was composed solely of male subjects, it was not possible to analyze whether gender is a variable that changes or affects measurements quality of life in alcoholics. According to Foster and cols., this variable contributes modestly to differences of perceptions of quality of life. The authors emphasize that the

5 477 impact of the sex variable in the quality of life construct of alcohol dependent patients is not fully known, but that it is probably a variable worthy of further investigation [29]. This study suggests that the WHOQoL-BREF instrument is capable of discriminating differences in quality of life scores in male subjects dependent on alcohol, displaying satisfactory psychometric properties, even in a small sample of individuals. Therefore, our data showed that alcoholism affects multiple areas in the life and the WHOQoL-BREF is utile to assess quality of life in this population. Acknowledgement This work was partially supported by the Research Fund of Hospital de Clı nicas de Porto Alegre, Brazil. Three of is authors (AFBSL, FP & RB) are members of the Center for Drug and Alcohol Research of the Federal University of Rio Grande do Sul. This paper is part of a master thesis named Quality of life in male alcohol dependent patients, presented at the Graduate Program in Medical Clinics, Universidade Federal do Rio Grande Sul, Brazil. References 1. Monteiro MG, Monteiro MA, Santos BR. Detecção do alcoolismo na população geral através do questionário CAGE: O que mudou em cinco anos? Revista ABP-APAL 1991; 13(Suppl 2): Almeida LM, Coutinho ESF. Prevalência do consumo de bebidas alcoólicas e de alcoolismo em uma região metropolitana do Brasil. Rev Sau de Pu blica 1993; 27(Suppl 1): Morgado AF, Coutinho ESF. Dados de epidemiologia descritiva de transtornos mentais em grupos populacionais do Brasil. Cadernos de Sau de Pu blica 1985; 1(Suppl 3): Santana VS, Almeida Filho N. Alcoolismo e consumo de álcool: Resumo de achados epidemiológicos. Revista ABP- APAL 1987; 9(Suppl 1): Fleck MPA, Soares HH. Estudo preliminar da prevalência de alcoolismo em pacientes internados no Hospital de Pronto Socorro de Porto Alegre. R. Psiquiatr.RS 1990; 12(Suppl 2): Nunes SOB, Onishi LO, Hashimoto SM, et al. A história familiar e a prevalência de dependência de álcool e tabaco em área metropolitana na região Sul do Brasil. Rev Psiq Clin 1999; 26(Suppl 3): Soares KVS, Busnello EA, Coutinho ESF, Almeida Filho N, Andreolli SB, Mari J. Comorbidades nos Transtornos Depressivos na População de Três Centros Urbanos Brasileiros.Neurobiol 1995; 58(Suppl 3): Rego RA, Oliveira ZMA, Berardo FAN, Oliveira MB, Ramos LR. Epidemiologia do Alcoolismo. Prevalência de positividade do teste CAGE em inquérito domiciliar no Município de Sa o Paulo. Revista ABP-APAl 1991; 13(Suppl 2): Schuckit MA. Alcoholism: An introduction. In: Schuckit MA (ed), Drug and Alcohol Abuse. 5th ed. New York: KA/ PP, 2000: Longabaugh R, Mattson ME, Connors GJ. Quality of Life as an Outcome Variable in Alcoholism Treatment Research. J Stud Alcohol 1994; 12: Metzger DS, Davis RF, O Brien C. Substance Abuse Disorder In: Spilker B (ed.), Quality of life and Pharmaeconomics in clinical Trials. 2nd ed. Philadelphia: Lippincott-Raven, 1996: pp Schipper H, Clinch J, Olweny CLM. Quality of Life Studies: Definitions and Conceptual Issues. In: Spilker B (ed), Quality of life and Pharmaeconomics in clinical Trials. 2nd ed. Philadelphia: Lippincott-Raven, 1996: pp Volk RJ, Cantor SB, Steinbauer JR, Cass AR. Alcohol Use Disorders, Consumption Patterns And Health-Related Quality Of Life Of Primary Care Patients. Alcohol Clin Exp Res 1997; 21(Suppl 5): Holcombh, Parker JC, Leong GB. Outcomes of Inpatients Treated on a VA Psychiatric Unit and Substance Abuse Treatment Unit Psychiatric Services 1997; 18(Suppl 5): Spitzer Rl, Kroenke K, Linzer M, et al. Health Related Quality of Life in Primary CPare Patients with Mental Disorders. JAMA 1995; 274(Suppl 19): Patience D, Bucxton M, Shick J, Howlett H, McKenna M, Ritson B. The SECCAT Survey: II The Alcohol Related Problems Questionnaire as a Proxy for Resource Costs and Quality of Life in Alcoholism Treatment. Alcohol Alcoholism 1997; 32(Suppl 1): Folstein Mf, Folstein SE, McHugh. Mini-mental State A Practical Method for Grading The Cognitive State of Patients For the Clinician. J Psychiatr Res 1975; 12: Amorim P. Mini International Neuropsychiatric Interview (MINI): Validaça o de entrevista breve para diagnóstico de transtornos mentais. Revista Bras Psiquiatr 2000; 22(Suppl 3): Pechansky F, Soibelman M, Goldin JR. Modificaço es no Escore do Questionário SADD apo s Aplicaço es Repetidas. ABP-APAL 1989; 11(Suppl 1): Pechansky F. Avaliação da Severidade da Dependência do Álcool: Problemas Relacionados a Padrões Objetivos e Subjetivos de Estimativa. R Psiquiatr RS 1990; 12(Suppl 3): Pechansky F, Soibelman M, Jacques SMC. Estimativas Para a Severidade da Dependência do Álcool e Possibilidade de Melhora: Discord^ancia entre Pacientes e Psiquiatras. R Psiquiatr RS 1994; 16(Suppl 3):

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