Keywords
psychotherapy
empirical research
methodological quality
research design
online research
post-stratification
digital research technologies
How to Cite
Abstract
Background. The contemporary development of clinical psychology and psychotherapy is characterized by increasing requirements for evidence-based practice, an expanding range of research designs, and the active integration of digital technologies. At the same time, the methodological quality of empirical research is becoming increasingly important, as research findings provide the basis for evaluating the effectiveness of psychological and psychotherapeutic interventions, developing clinical guidelines, and making evidence-informed decisions in practice. Particular attention is required to issues related to internal and external validity, sample representativeness, control of systematic biases, the psychometric quality of assessment instruments, the appropriateness of statistical analyses, and the organization of online research.
Objective. To synthesize current scientific evidence on methodological problems in empirical research in clinical psychology and psychotherapy, identify major methodological gaps, determine promising directions for addressing them, and provide an integrated perspective on ensuring the methodological quality of such research.
Methods. A narrative review of scientific publications was conducted in accordance with the methodological recommendations of the Scale for the Assessment of Narrative Review Articles (SANRA). Relevant literature was searched in Scopus and Web of Science, primarily covering the period from 2020 to 2026, using English- and Ukrainian-language search terms. The review included empirical studies, systematic and narrative reviews, meta-analyses, scholarly books, and selected book chapters addressing methodological problems in research in clinical psychology and psychotherapy.
Results. The key methodological problems identified were related to the justification of research design, the formation of representative samples, the selection of valid and reliable psychodiagnostic instruments, the control of systematic biases, appropriate statistical methods, and the use of digital technologies. Particular attention was given to methodological issues in psychotherapy effectiveness research, the role of randomized controlled trials, and current trends in the digitalization of psychotherapeutic practice. Quantitative and qualitative online methods, the advantages and methodological risks of digital data collection, participant self-selection, and the representativeness of online samples were analyzed. Participant recruitment strategies, quota sampling, and post-stratification as a statistical approach to partially correcting discrepancies between sample composition and the characteristics of the target population were considered. The major methodological problems and approaches to addressing them were systematized. Based on the synthesis of the reviewed literature, a conceptual model for ensuring the methodological quality of empirical research in clinical psychology and psychotherapy was proposed. Methodologically sound research design, representative sampling, valid psychodiagnostic instruments, control of systematic biases, appropriate contemporary statistical methods, and digital research technologies contribute to improving the reliability, validity, and reproducibility of findings in clinical psychology and psychotherapy research.
Conclusions. Ensuring the methodological quality of clinical psychology and psychotherapy research requires a comprehensive approach encompassing all stages of the research process. The integration of methodologically sound research design, representative sampling, valid psychodiagnostic instruments, control of systematic biases, contemporary statistical approaches, and digital technologies is essential for obtaining reliable, reproducible, and practically meaningful scientific findings.
Keywords: clinical psychology, psychotherapy, empirical research, methodological quality, research design, online research, post-stratification, digital research technologies.
Received: 4 May 2026
Accepted: 25 June 2026
Published: 30 July 2026
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