Abstract
Negative effects (NE) can be defined as all changes experienced during or after the psychotherapeutic process, considered negative by the client, which are attributed by the client to the performed clinical interventions. This work aimed to conduct a systematic review about NE in clinical trials, investigating the definition and assessment of the construct. A secondary aim was to verify which approaches to psychotherapy were used in the selected studies and which had the greatest NE. Using PRISMA criteria to report systematic reviews, a survey was conducted by two independent researchers between April and July 2020 in the PubMed, Web of Science, PsycINFO and Science Direct databases to identify clinical trials evaluating the NE of psychotherapeutic interventions. Results showed difficulties regarding the consensus towards the definition of the construct and the standardisation of the measurement of NE may culminate in the difficulty of accessing the risks of the offered interventions. Four of six studies investigated differences between approaches to psychotherapy and, among them, which had the greatest NE. Results varied according to the approaches to psychotherapy investigated by each study.