Geänderte Inhalte

Introduction: Psychology is shifting from group-based designs to idiographic approaches, raising questions about suitable analytical methods. While a full review across subfields is beyond this paper’s scope, psychotherapy research serves as a representative example. Single Case Experimental Designs (SCEDs) can be used to estimate meaningful intervention effects for individuals, but selecting among many evaluation methods is challenging. This study provides a comprehensive overview of SCED analysis methods, assessing their strengths and limitations to guide scientific and clinical decision-making. Method: A literature search was conducted to identify methods suited to compare a baseline to an intervention phase, to be used with idiographic or non-standardized items and with repeated evaluations during ongoing therapy. To illustrate these methods, data from a clinical single case is analyzed and interpreted as an example. Results: Seventeen relevant peer-reviewed articles on SCEDs and clinical decision-making were identified. NAP, Tau-BC, and the Bayes Factor emerged as particularly suitable methods, though further validation is needed. Method selection highly depends on data characteristics, with nonoverlap approaches preferred for non-parametric data and SMA or DARCI suitable for small datasets. The case study revealed challenges in interpreting and combining different methods, emphasizing the need for clearer guidelines. Discussion: While no single method is universally optimal, future research should refine existing approaches, compare them systematically, and integrate clinical perspectives to develop clearer guidelines. Beyond identifying a gold standard, ensuring practical implementation remains a key challenge.

Most people experience positive involuntary mental imagery (IMI) frequently in daily life; however, evidence for the importance and effects of positive IMI is largely indirect. The current study adapted a paradigm to experimentally induce positive IMI in participants’ daily lives. This could in turn provide a means to directly test positive IMI’s effects. In a within-subjects design, participants (N = 41) generated positive mental images (imagery condition) and sentences (verbal condition) from photo cues, half of which participants provided from their own living environment. Participants then recorded involuntary memories of the previously generated images or sentences in a seven-day diary, before returning to the lab and completing some measures including an involuntary memory task. In the diary, participants reported more involuntary memories from the imagery condition than from the verbal condition, and more involuntary memories from their own photos compared to the other photos. A more mixed pattern of findings was found across other tasks in the lab. The study indicates that the paradigm can be used as a means to induce positive IMI and that using photos as the basis for generating positive imagery increases the amount of IMI in daily life. Theoretical and potential clinical implications are discussed.