Drug Abstinence Self-Efficacy Scale (DASES): psychometric properties of the Farsi version

Substance use disorder, a chronic, persistent disease associated with personal, familial, and social dysfunctions, is one of the world’s more challenging health care problems [1‐3]. The prevalence of substance use has been fixed at around 0.5% of the global population over the past decade, but it differs by area and type of drug used. East and Southeast Asia are among the main centers for the production and transportation of illegal drugs [4]. Iran shares a border with Afghanistan, a major manufacturer of narcotics, which facilitates the importation of illicit drugs to Iran [3, 5]. As in other Islamic countries, substance use is forbidden in Iran based on Islamic law, customs, and social values [6]. Despite this, Iran ranks high in opium use; about 1.8–3.3 million persons use drugs annually [3], and drug and alcohol disorders make up about 2% of the total disease burden [7]. As Iran is recognized as having among the highest rates of drug use for heroin, cannabis, and methamphetamine, it is not surprising that drinking alcohol and using drugs comprise almost 2% of the country’s disease burden [8].

Substance use prevention, particularly primary prevention, is the most economical and potentially effective solution to this problem [9], but clear indications of the characteristics of substance use disorder are a prerequisite for substance use prevention. Successful methods of ending drug use are often based on behavioral change models and theories, and two cognitive-behavioral theories have been suggested that may explain the relapse process and that offer important suggestions for designing effective management approaches [10, 11]. Albert Bandura developed the self-efficacy theory based on social cognitive theory, according to which individuals can influence their setting and environment rather than merely reacting to them. Self-efficacy aligns with this as it relies on individuals’ belief in their capacity to execute the behaviors needed to produce specific results [12]. According to the theory, if individuals do not believe they have the capacity to implement the behavior needed to reach the desired goal, they will put forth minimal effort or not engage in that behavior. Self-efficacy beliefs are also believed to vary depending on the domain of functioning and the circumstances of the behavior’s occurrence [10, 12].

The theory suggests that self-efficacy can alter behavior through the recognition of background signs and through encouragement to achieve a specific result. Effective interventions to decrease drug use or other addictive behaviors are supposed to strengthen efficacy beliefs related to a person’s ability to reduce the desire to take part in such behaviors [12]. Self-efficacy is a key factor in treating substance use as individuals must be confident of their ability to stop using drugs. Without self-efficacy, treatment can be challenging. In fact, people who use drugs may believe that they cannot stop using substances.

In the context of substance use, self-efficacy can influence a people’s ability to withdraw from drug use when they are close to other persons who consume drugs, are pressured by others to use, or are in specific settings [13]. It is often hard for people who use drugs to resist the temptation to use, and strong self-efficacy beliefs may help them resist [14].

Based on social cognitive theory, many instruments have been developed to assess the degree to which interventions can change personal behavior. One such scale in substance abstinence, based on the self-efficacy structure of Bandura’s social cognitive theory, is the Drug Abstinence Self-Efficacy Scale (DASES) [15]. DASES is a 20-item self-report survey that measures confidence in one’s ability to abstain from using drugs in specific situations. The test results can help in assessing whether an individual is ready for drug treatment and in determining the right mode of treatment. High scores on the DASES indicate that individuals have more confidence in their ability to abstain from drugs. Conversely, low scores indicate that they do not believe they can resist the temptation to use drugs [15]. This information can help medical professionals determine the treatment path and aid therapists in improving self-efficacy. DiClemente et al. (1994) developed the Alcohol Abstinence Self-Efficacy Scale (AASES), which was adapted by Hiller and colleagues (2000) [15] into the DASES [16]. The DASES has been validated in other countries [15], but no study has validated it in Iran.

As cultural and linguistic factors may impact how respondents complete the original version of the DASES, it is important to reevaluate the validity and reliability of DASES in different cultures, such as that of Iran. Therefore, the present study measures the psychometric properties of the Iranian version of the DASES to support abstinence in Iranian drug-addicted persons.

Additionally, a test–retest analysis was conducted to assess the stability of the DASES. The results found a satisfactory threshold. The ICC ranged from 0.75 to 0.98 for the dimensions of the DASES, supporting the scale’s stability. The results are presented in Table 3.

This study examined the factor validity, dimensionality, and reliability of the DASES among Iranian people who use drugs. Overall, the findings indicate that the psychometric characteristics of the Farsi version of the DASES are good. Consistent with other studies, we found a four-factor structure [15, 16], indicating that improvement in self-efficacy happens through several points and consequently demonstrating the role of individual dissimilarities, which urges further study within this population. Furthermore, the development of theory-based scales can serve as an important prerequisite for the assessment of any educational program. Consequently, we consider the results of the present study to be valuable for clients who are part of a drug-control plan.

Overall, the study found satisfactory psychometric properties for the DASES, with the CVI and CVR indicating that its content validity was good. Furthermore, the results of the EFA and CFA revealed a good structure for the DASES, with the EFA showing that the four-factor structure of the DASES accounted for 64.72% of the total observed variance. The results of the EFA were compatible with those achieved by the English version of the DASES. This shows that the DASES is useful for revealing various aspects of the health concerns influenced by drug use. As expected, this study indicated a four-factor solution for the Iranian version of the DASES, including Negative Affect, Social Pressure, Cravings and Urges, and Physical and Other Concerns about Using Drugs subscales.

The CFA also examined whether coherence exists between the information and the theoretical structure. The CFA revealed good fit indices for the existing model and demonstrated the acceptable convergent validity of the four subscales of the DASES (i.e., Negative Affect, Social Pressure, Cravings and Urges, and Physical and Other Concerns about Using Drugs). These findings related to the CFA are consistent with the model from the original instrument developed by Hiller et al. (2000) [15], showing that the DASES is reliable when used by Farsi-speaking addicted persons.

Additionally, acceptable levels of the Cronbach’s alpha and the ICC were found, and the good stability and reliability of the DASES were demonstrated. The internal consistency of the DASES, as evaluated by the Cronbach’s alpha, displayed a suitable reliability for the four dimensions in accordance with the original study [15]. Moreover, after 35 male participants who use drugs were tested over a two-week period, the test–retest reliability coefficient of the DASES was a satisfactory 0.78. It is generally held that assessments of repeatability for group comparisons should be at least 0.70 [17, 34], so our results clearly show that the DASES has appropriate stability in the short term; however, it has yet to be determined whether it is stable over the long term. Overall, the findings indicate satisfactory psychometric properties for the DASES.

The DASES provides an understanding of the processes by which addicted persons attempt to modify their addictive drug use behavior. The development of theory-based scales serves as an important prerequisite for the assessment of any educational program. Consequently, we consider the results from the present study to be valuable for clients who are taking part in a drug-control plan.

Although the results of the current study reveal several benefits, some limitations must be considered. The first concerns the truthfulness of the clients’ responses due to the self-reported nature of the answers. The generalizability and sample size constitute other limitations. The sample was limited to a group of 400 (both EFA and CFA) men who use drugs, and it is uncertain whether we would attain the same results if a larger sample of both male and female participants who use drugs was employed. Consequently, the present findings may not be able to measure gender differences regarding the psychometric properties of the DASES. In future studies with a larger group of both male and female people who use drugs, researchers should consider measuring whether motivations to cease drug use are similar between the genders, whether gender affects acceptance of treatment, and whether the current findings remain valid. Furthermore, it would be interesting for future studies with a larger sample to test whether the psychometric properties of the instrument persist with alternative measures of reliability and validity (e.g., test–retest validity). Finally, the present study included only addicted persons who were referred to clinics. Future studies should also measure the psychometric properties of the Iranian version of the DASES in Iranian addicted persons who were referred to drop-in centers.

The findings suggest that the Farsi version of the DASES is a valid, reliable measure to assess drug use among Iranian addicted men. The DASES is important because it provides standardized information about substance use self-efficacy behaviors. The use of a procedure and method accepted in the scientific literature makes available the assessment of information garnered from diverse backgrounds. It is suggested that the DASES should be further assessed in both dissimilar areas of Iran and in different populations and cultures. When a valid and reliable instrument is devised, it may be applied to assess the consequences of intervention research, and, as previously stated, it should be assessed among dissimilar populations and backgrounds. The scale that was assessed in the current study will contribute positively to the progress of more effectual, evidence-based anti–substance-use plans for the population. Furthermore, the Farsi version of the DASES may help health care workers to find and plan health strategies that are useful and targeted to patients of particular statuses.