162 All rights are reserved by UIJRT.COM. United International Journal for Research & Technology Volume 04, Issue 03, 2023 | Open Access | ISSN: 2582-6832 Assessing Drug Abuse Treatment and Rehabilitation Through Psychological Functioning, Mental Wellbeing, and Life Satisfaction: Scales Adaptation and Development Argel B. Masanda National University Philippines Email: abmasanda@nu-baliwag.edu.ph Abstract— Drug abuse is one of the perennial global pandemics since the 1960s, and persons who use drugs (PWUDs) have been subjected to an array of treatment courses and rehabilitation efforts. This study underscored the adaptation and development of assessment tools to measure progress among PWUDs undertaking drug abuse treatment and rehabilitation through these frontiers. Based on the literature, people engaging in illicit drug use often experience difficulties in terms of their affective, behavioral, and cognitive functioning as well as in their mental wellbeing and life satisfaction. Hence, through a Bootstrap Approach to test construction and guided by strict ethical procedures, 100 college students and 100 PWUDs from a treatment and rehabilitation center were selected to estimate the psychometric properties of the adapted Warwick-Edinburg Mental Wellbeing Scale (Tennant et al., 2007) and Life Satisfaction Scale (Deiner et al., 1985) and the developed Psychological Functioning Scale. Based on Pearson r statistics, the translations of the W-EMWS, r(92) = 0.95, p < 0.01, and the LSS, r(92) = 0.82, p < 0.01, were statistically accurate. Cronbach’s alphas of both tests were also very strong (W-EMWS: α = 0.92; LSS: α = 0.87) similar with the subscales of the PFS (affective: α = 0.87; behavioral: α = 0.66; cognitive: α = 0.89). These results indicated that the three scales are all statistically sound and thus can be used to reliably measure the progress of the PWUDs who are recovering from illicit drug use. Pertinent conclusions were thereby drawn, and various recommendations were duly suggested. Keywords— Psychological Functioning, Mental Wellbeing, Life Satisfaction, Drug Abuse, Persons Who Use Drugs. INTRODUCTION Addiction is often linked to other mental health issues though there is no clear directionality to this relationship. For instance, Volkow (2004) identified that people who have mood or anxiety disorders are almost twice as likely to have a substance use disorder; people who suffer from substance use disorders are approximately twice as likely to also struggle with a mood or anxiety disorder. It is not conclusive which disorder is causing the other, but the relationship is strong nevertheless. Depression is one of the most common long-term mental health disorders associated with substance use disorder (Volkow 2004; NIDA, 2016); others include anxiety (NIDA, 2017a) and paranoia (NIDA, 2017b). Other psychological effects of drug addiction include wild mood swings, hallucinations, violence, decreased pleasure in everyday life, confusion, mental illness complications, psychological intolerance, and increased risky behavior (Tracy, 2012). Furthermore, substance use can also increase a user's risk of developing a mental disorder though considerably speaking, genetic predisposition plays a vital role in this case as "substance addiction, and mental illness is disorders that develop. Emotional stress can also be one of the impacts of illicit drug use, and the inability to control compulsive behaviors may also lead to more problems for those who use the illicit substance (Szalavitz, 2016). It results from the brain's inability to function normally as it seeks higher and higher doses of the substance until it leads to addiction. Rosenfeld (2017) identified drug addiction as associated with "trauma caused by (or the result of) a repressed, buried event or series of events in their past." He further noted that addiction is an "escape mechanism, a powerful source of pleasure to counter a powerful cause for emotional stress." Based on the Diagnostic and Statistical Manual of Mental Disorders of the American Psychiatric Association (2013), a person who is struggling with a SUD possesses the following diagnostic criteria: "Taking a substance in higher doses or for longer than intended, wanting to quit using but being unable to, spending much time trying to get, use, or recover from