Post-hoc power analysis: a conceptually valid approach for power based on observed study data.

Power analysis is a key component of planning prospective studies such as clinical trials. However, some journals in biomedical and psychosocial sciences request power analysis for data already collected and analysed before accepting manuscripts for publication. Many have raised concerns about the conceptual basis for such post-hoc power analyses.

Comparison of the APAS Independence Automated Plate Reader System with the Manual Standard of Care for Processing Urine Culture Specimens.

Urine cultures are among the highest-volume tests in clinical microbiology laboratories and usually require considerable manual labor to perform. We evaluated the APAS Independence automated plate reader system and compared it to our manual standard of care (SOC) for processing urine cultures. The APAS device provides automated image interpretation of urine culture plate growth and sorts those images that require further evaluation.

Liver Stiffness on Magnetic Resonance Elastography and the MEFIB Index and Liver-Related Outcomes in Nonalcoholic Fatty Liver Disease: A Systematic Review and Meta-Analysis of Individual Participants.

Background & Aims: Magnetic resonance elastography (MRE) is an accurate biomarker of liver fibrosis; however, limited data characterize its association with clinical outcomes. We conducted an individual participant data pooled meta-analysis on patients with nonalcoholic fatty liver disease to evaluate the association between liver stiffness on MRE and liver-related outcomes.

Methods: A systematic search identified 6 cohorts of adults with nonalcoholic fatty liver disease who underwent a baseline MRE and were followed for hepatic decompensation, hepatocellular carcinoma, and death.

The Relationship Between Loneliness and Positive Affect in Older Adults.

Objective: To establish whether positive affect (PA) is uniquely associated with loneliness and other social functioning variables beyond negative affect (NA) among older adults.

Methods: Four hundred and twenty-eight participants (aged 60+ years old, 82% White, and 48% female) were recruited using random digit-dialing and completed scales for loneliness (UCLA Loneliness Scale), companionship (PROMIS scale), satisfaction with discretionary social activities (PROMIS scale), PA (Center for Epidemiologic Studies [CES] Happiness Scale), and NA (CES-Depression scale and Brief Symptom Inventory-Anxiety Subscale).

Results: Multiple linear regression models found PA to be a significant predictor of lower loneliness where the effect of PA on loneliness is dependent on the level of NA; a large effect size at the mean level of NA, which becomes attenuated when NA increases.