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The Crack Use Relapse Scale (CURS): development and psychometric validation

Abstract

Objective:

To report the development and validation of the Crack Use Relapse Scale (CURS) in an inpatient population.

Methods:

A pilot study with 30 male crack users was conducted to generate 35 sentences related to the construct of interest. A five-point Likert scale including 25 items and, initially, nine theoretical factors was generated and utilized in a cross-sectional study with a sample of 333 hospitalized male crack users.

Results:

Overall Cronbach's alpha was α = 0.86. The exploratory factor analysis (EFA) with oblimin rotation kept the 25 items (factor loadings > 0.40) and six definitive factors, which explained 62.1% of the total variance.

Conclusions:

The six-factor model yielded by the EFA of the CURS reflects the various dimensions of the construct, assigning satisfactory values and demonstrating good psychometric properties, including validity and reliability.

Relapse; crack users; scale; validation


Introduction

Health is a broad and multifactorial concept in the context of psychoactive substance use, and particularly in the context of crack cocaine use. Prior studies1. Marlatt GA, Gordon JR. Prevenção de recaída: estratégia e manutenção no tratamento de comportamentos aditivos. Porto Alegre: Artes Médicas; 1993. 2. Bandura A. Self-efficacy: the exercise of control. New York: Freeman; 1997. 3. Schenker M, Minayo MCS. [Risk and protective factors and drug use among adolescence]. Cien Saude Colet. 2005;10:707-17. 1-44. Noto AR, Baptista MC, Faria ST, Nappo SA, Galduróz JCF, Carlini EA. [Drugs and health in the Brazilian press: an analysis of articles published in newspapers and magazines]. Cad Saude Publica. 2003;19:69-79. have shown that a variety of factors are directly involved in the dependence behavior and relapse process, including family, criminality, ties with the drug trade, availability of housing, personal relationships, financial issues, spirituality, ability to cope with high-risk situations, and clinical aspects, such as psychiatric comorbidities and craving.55. Kessler F, Pechansky F. [A psychiatric view on the crack phenomenon nowadays]. Rev Psiquiatr RS. 2008;30:96-8.

However, there is a lack of specific, reliable, validated research instruments for the assessment of the psychological, psychiatric, and social constructs involved in the use of crack.66. Pasquali L. Psicometria. Petrópolis: Vozes; 2003. Such instruments could be helpful in the diagnosis and assessment of crack use relapse, a relatively frequent occurrence in the first weeks after discharge, either from outpatient or inpatient rehabilitation.77. Formigoni MLOS, Castel S. [Rating scales of drug dependence: general aspects] Rev Psiquiatr Clin. 1999;26:5-31.

The objective of the present study was to describe the development and psychometric validation of an instrument (Crack Use Relapse Scale - CURS) designed to assess the risk factors that may lead crack users to relapse shortly after discharge from rehabilitation treatment. This is an attempt to support the development of new strategies to improve self-efficacy and the skills required to face relapses of crack cocaine use. We recently published a qualitative study88. Pedroso RS, Kessler F, Pechansky F. Treatment of female and male inpatient crack users: a qualitative study. Trends Psychiatry Psychother. 2013;35:36-45. with 14 crack users receiving inpatient treatment. These participants were interviewed and their reports on factors associated with relapse were analyzed to serve as the basis for the construction of the instrument described herein.

Methods

Development of the scale

Pilot study

Thirty male crack users were interviewed to generate 35 sentences related to the construct of interest. Content and semantic validation were obtained later via a focus group of eight male crack users, as well as an expert panel of 10 drug dependence specialists. After discussion, the group selected 25 sentences, which were adapted by the principal investigator into 25 items, divided into nine theoretical factors: family and emotional aspects; negative feelings; positive feelings; craving; physical aspects; treatment; legal aspects; social aspects; and coping. The entire pilot study procedure was described in detail elsewhere.88. Pedroso RS, Kessler F, Pechansky F. Treatment of female and male inpatient crack users: a qualitative study. Trends Psychiatry Psychother. 2013;35:36-45.

Psychometric validation of the scale

Using a cross-sectional design, a convenience sample of 333 male crack users hospitalized in a public psychiatric hospital in Porto Alegre, Brazil, was recruited. Sample size was calculated on the basis of the number of items of the study instrument. Therefore, our sample met the established criteria for exploratory factor analysis (EFA), with a ratio of 10 subjects for each item of the 25-item scale.99. Hair JF, Tatham RL, Anderson RE, Black W. Análise multivariada de dados. Porto Alegre: Bookman; 2005.

Most participants were white (74.47%). Only a minority of subjects claimed to have a marital relationship (16.52%). Mean age (25.9±7.96 years) and educational attainment (median, 12.0 years of formal education; interquartile range: 12.0-13.0) were also noteworthy characteristics.

All subjects had a diagnosis of cocaine dependence - specifically, crack cocaine dependence.1010. American Psychiatric Association. Manual diagnóstico e estatístico de transtornos mentais. Texto revisado - DSM-IV-TR - 4a edição. Porto Alegre: Artmed; 2002. No subjects were excluded from analysis.

Instruments

  • Semi-structured interview: conducted to evaluate the sociodemographic profile of the sample and to describe the pattern of psychoactive substance use.

  • CURS: a five-point Likert-type scale1111. Likert R. A technique for the measurement of attitudes. Arch Psychol. 1932;22:1-55. with 25 items. Instruction to respondents: “Read each item and circle the number that best describes how much you disagree or agree with the statements related to your use of crack during the past 6 months.”

Data analysis

Cronbach's alpha was used to test the reliability of internal consistency (Table 1). We analyzed each factor individually and the 25-item scale as a whole. The kappa coefficient was used to assess inter-rater reliability. The Kaiser-Meyer-Olkin test (KMO) was used to evaluate sampling adequacy, and Bartlett's test was used to test for sphericity of the CURS and to assess the suitability of the data for EFA.

Table 1
Exploratory factor analysis and assessment of reliability (factor loadings > 0.40 after oblimin rotation)

Ethical aspects

The study was approved by the Institutional Review Board of the Hospital de Clínicas de Porto Alegre.

Results

The KMO test (0.774) was used to evaluate the adequacy of the data, and Bartlett's test (p < 0.001) rejected sphericity, which is indicative of significant correlations between the items of the CURS. The data therefore met the assumptions for EFA, which was performed using oblimin rotation. EFA kept the 25 items with factor loadings > 0.40 (Table 1) and six definitive factors, which explained 62.1% of the total variance. The six factors are important because they express the aspects reported by crack users to be involved in their relapse.88. Pedroso RS, Kessler F, Pechansky F. Treatment of female and male inpatient crack users: a qualitative study. Trends Psychiatry Psychother. 2013;35:36-45.

Discussion

Our findings show that the CURS is based on a valid model for measuring the factors that influence relapse among crack users, as demonstrated by satisfactory psychometric parameters. EFA immediately established the good fit of the constructed model, distributing the nine initial theoretical factors across a six-factor model. This shows that the original scale had an appropriate a priori model, as none of the essential concepts of the CURS were removed; that is, the concepts were regrouped without losing the meaning assigned to the initially constructed domains.

Although EFA retained all 25 items of the scale with factor loadings > 0.40 and data showed that all items exceeded this parameter and were thus fully satisfactory,66. Pasquali L. Psicometria. Petrópolis: Vozes; 2003.,1212. Fachel JMG, Camey S. Avaliação psicométrica: a qualidade das medidas e o entendimento dos dados. In: Cunha JA, editor. Psicodiagnóstico-V. Porto Alegre: Artmed; 2000. p. 158-70. we decided that the wording of three items should be modified. Item 13, “Exchange of sex for crack when the craving strikes,” was modified when we realized it contained two complex constructs in a single statement. We simplified this item, replacing it with the expression “Exchange of sex for crack,” which facilitated understanding by respondents. Item 16, “Difficulty accessing treatment in the public health service,” was simplified to read “Difficulty accessing treatment.” Item 25, “Lack of spirituality,” was modified to read “Spirituality,” a broader term.

EFA was performed with oblimin rotation to facilitate factor readings. This analysis demonstrated high factor loadings for one factor and lower loadings for others; thus clearly defining the clusters of variables that compose each factor of interest. On the basis of these results, item 21, “Favorable social environment for the consumption of crack,” was distributed across two factors; although its factor loading was higher in Factor 2 - Coping, we chose to keep it in Factor 4 - Legal and social aspects, as it was conceptually more adequate to explain the construct assessed by this domain.1313. Araujo RB, Pansard M, Boeira BU, Rocha NS. Coping strategies for craving management in crack dependents. Rev. HCPA & Fac Med Univ Fed Rio Gd do Sul. 2010;30:36-42.

We are aware of some limitations of our study. Although a heterogeneous, diverse sample is advisable for validation studies, our sample was entirely male, as male crack users are still more likely to receive treatment in Brazil.88. Pedroso RS, Kessler F, Pechansky F. Treatment of female and male inpatient crack users: a qualitative study. Trends Psychiatry Psychother. 2013;35:36-45. The facility where the study was conducted has a dedicated unit for the treatment of male users, but no such unit for women. Nevertheless, we believe studies with female samples would be important.

It bears stressing that this study presents satisfactory results for the first-ever scale developed for the assessment of crack use relapse. The CURS is a short scale that can be easily and quickly administered (about 7 minutes), which is key for crack users. At least partially, this scale can now be used as an alternative to bridge the gap in preventive strategies for coping with high-risk situations in this population. According to the media, over 70% of crack cocaine users treated at inpatient drug rehab facilities will relapse after discharge. However, scientifically sound data on what really happens to this population after discharge are still lacking.88. Pedroso RS, Kessler F, Pechansky F. Treatment of female and male inpatient crack users: a qualitative study. Trends Psychiatry Psychother. 2013;35:36-45. The CURS proved adequate for assessment of risk factors associated with relapse after discharge. It can also be used for follow-up interviews within a psychosocial treatment model,1414. Conner M, Norman P. Predicting health behavior. Buckingham: Open University Press; 1996. which is an essential intervention for following the trajectory of crack users after discharge from rehabilitation and, perhaps, even modifying the now almost-certain bad outcome (i.e., relapse).

Finally, we believe that effective prevention of relapse among crack users can be achieved based on the users' knowledge of their vulnerabilities. This is in agreement with the health belief model, according to which individuals are able to perform preventive behaviors related to a certain condition merely because they believe they are susceptible to such condition and subsequently take preventive action to modify their behavior. Therefore, the importance of the CURS lies on the fact that it provides such data for researchers and clinicians working with crack cocaine users.1515. Rosenstock IM, Strecher VJ, Becker MH. Social learning theory and the Health Belief Model. Health Educ Q. 1988;15:175-83.

Acknowledgement

Funding for this study was provided by Brazilian Secretariat for Drug Policies (SENAD) (project no. 10/0002).

References

  • 1
    Marlatt GA, Gordon JR. Prevenção de recaída: estratégia e manutenção no tratamento de comportamentos aditivos. Porto Alegre: Artes Médicas; 1993.
  • 2
    Bandura A. Self-efficacy: the exercise of control. New York: Freeman; 1997.
  • 3
    Schenker M, Minayo MCS. [Risk and protective factors and drug use among adolescence]. Cien Saude Colet. 2005;10:707-17.
  • 4
    Noto AR, Baptista MC, Faria ST, Nappo SA, Galduróz JCF, Carlini EA. [Drugs and health in the Brazilian press: an analysis of articles published in newspapers and magazines]. Cad Saude Publica. 2003;19:69-79.
  • 5
    Kessler F, Pechansky F. [A psychiatric view on the crack phenomenon nowadays]. Rev Psiquiatr RS. 2008;30:96-8.
  • 6
    Pasquali L. Psicometria. Petrópolis: Vozes; 2003.
  • 7
    Formigoni MLOS, Castel S. [Rating scales of drug dependence: general aspects] Rev Psiquiatr Clin. 1999;26:5-31.
  • 8
    Pedroso RS, Kessler F, Pechansky F. Treatment of female and male inpatient crack users: a qualitative study. Trends Psychiatry Psychother. 2013;35:36-45.
  • 9
    Hair JF, Tatham RL, Anderson RE, Black W. Análise multivariada de dados. Porto Alegre: Bookman; 2005.
  • 10
    American Psychiatric Association. Manual diagnóstico e estatístico de transtornos mentais. Texto revisado - DSM-IV-TR - 4a edição. Porto Alegre: Artmed; 2002.
  • 11
    Likert R. A technique for the measurement of attitudes. Arch Psychol. 1932;22:1-55.
  • 12
    Fachel JMG, Camey S. Avaliação psicométrica: a qualidade das medidas e o entendimento dos dados. In: Cunha JA, editor. Psicodiagnóstico-V. Porto Alegre: Artmed; 2000. p. 158-70.
  • 13
    Araujo RB, Pansard M, Boeira BU, Rocha NS. Coping strategies for craving management in crack dependents. Rev. HCPA & Fac Med Univ Fed Rio Gd do Sul. 2010;30:36-42.
  • 14
    Conner M, Norman P. Predicting health behavior. Buckingham: Open University Press; 1996.
  • 15
    Rosenstock IM, Strecher VJ, Becker MH. Social learning theory and the Health Belief Model. Health Educ Q. 1988;15:175-83.

Publication Dates

  • Publication in this collection
    Jul-Sep 2013

History

  • Received
    6 Nov 2012
  • Accepted
    17 Mar 2013
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