The relative effects of daily and weekly feedback on customer service behavior at a gas station were assessed using an ABC within-subjects design. Four critical service behaviors were identified and measured daily. After baseline (A), weekly feedback (B) was introduced, and daily feedback (C) was introduced in the next phase. The results indicated that the service behaviors improved when the weekly feedback was introduced and improved further when the daily feedback was introduced.

This study developed the Subjective Cognitive Function Decline Scale for Middle-aged South Koreans (SCFD-K), addressing the need for early detection of potential mild cognitive impairment. This study fills a gap in the existing research, which mainly targeted older demographics or generalized cultural differences. We conducted focus group interviews (FGIs) among 36 participants and with nine experts to answer basic questions related to cognitive decline, after which we developed a draft scale using the Delphi with another 15 experts. To examine the reliability and validity of the scale, an online survey of 2,000 people was conducted. An exploratory factor analysis identified four distinct factors, which are language, visuospatial function, personality/emotion, and memory, with a total of 20 items (Cumulative variance ratio = 57.76), and a confirmatory factor analysis validated the four-factor structure with a good model fit (CFI = 0.932, TLI = 0.921, RMSEA = 0.057, and SRMR = 0.042) and acceptable internal consistency (Cronbach's α = 0.735-0.907). This analysis established the SCFD-K as a reliable and valid tool for assessing cognitive decline among middle-aged South Koreans. The findings have key cultural implications and inform proactive interventions and shaping future healthcare strategies in South Korea.

Our research investigated how a smartphone application utilizing behavioral activation principles affects depression levels in young adult populations. A total of 67 participants aged 20–30 years with clinically significant depressive symptoms (CESD-11 ≥ 16) were divided into treatment (n = 31) and comparison conditions (n = 36) through randomization procedures. Participants in the experimental group engaged with a BA-based mobile application (Maummove) over an eight-week period, while those in the control group completed weekly assessments without intervention. Depression, perceived stress, and life satisfaction were measured at baseline and postintervention using the CESD-11, PSS, and SWLS, respectively. The results indicated that the experimental group exhibited significant reductions in depression (Cohen’s d = 1.03) and stress (Cohen’s d = 0.99) compared to the control group, which showed minimal changes. Improvements in life satisfaction were observed in the experimental group, with a smaller effect size (Cohen’s d = 0.23). Time-series analyses demonstrated that depressive symptoms decreased progressively throughout the intervention period, falling below the clinical cutoff by the seventh week. These findings provide preliminary evidence that BA-based mobile applications may offer a promising, accessible approach to reducing depressive symptoms and perceived stress in young adults, though replication in larger samples with longer follow-up periods is needed to establish generalizability. This study highlights the potential of digitally delivered BA interventions as a viable alternative or complement traditional mental health services, particularly for populations facing barriers to face-to-face care.