Peter E. Morris

The Publication Manual of the American Psychological Association (American Psychological Association, 2001, American Psychological Association, 2010) calls for the reporting of effect sizes and their confidence intervals. Estimates of effect size are useful for determining the practical or theoretical importance of an effect, the relative contributions of factors, and the power of an analysis. We surveyed articles published in 2009 and 2010 in the Journal of Experimental Psychology: General, noting the statistical analyses reported and the associated reporting of effect size estimates. Effect sizes were reported for fewer than half of the analyses; no article reported a confidence interval for an effect size. The most often reported analysis was analysis of variance, and almost half of these reports were not accompanied by effect sizes. Partial η2 was the most commonly reported effect size estimate for analysis of variance. For t tests, 2/3 of the articles did not report an associated effect size estimate; Cohen's d was the most often reported. We provide a straightforward guide to understanding, selecting, calculating, and interpreting effect sizes for many types of data and to methods for calculating effect size confidence intervals and power analysis.

OBJECTIVE: Immobilization and subsequent weakness are consequences of critical illness. Despite the theoretical advantages of physical therapy to address this problem, it has not been shown that physical therapy initiated in the intensive care unit offers benefit. DESIGN AND SETTING: Prospective cohort study in a university medical intensive care unit that assessed whether a mobility protocol increased the proportion of intensive care unit patients receiving physical therapy vs. usual care. PATIENTS: Medical intensive care unit patients with acute respiratory failure requiring mechanical ventilation on admission: Protocol, n = 165; Usual Care, n = 165. INTERVENTIONS: An intensive care unit Mobility Team (critical care nurse, nursing assistant, physical therapist) initiated the protocol within 48 hrs of mechanical ventilation. MEASUREMENTS AND MAIN RESULTS: The primary outcome was the proportion of patients receiving physical therapy in patients surviving to hospital discharge. Baseline characteristics were similar between groups. Outcome data are reflective of survivors. More Protocol patients received at least one physical therapy session than did Usual Care (80% vs. 47%, p < or = .001). Protocol patients were out of bed earlier (5 vs. 11 days, p < or = .001), had therapy initiated more frequently in the intensive care unit (91% vs. 13%, p < or = .001), and had similar low complication rates compared with Usual Care. For Protocol patients, intensive care unit length of stay was 5.5 vs. 6.9 days for Usual Care (p = .025); hospital length of stay for Protocol patients was 11.2 vs. 14.5 days for Usual Care (p = .006) (intensive care unit/hospital length of stay adjusted for body mass index, Acute Physiology and Chronic Health Evaluation II, vasopressor). There were no untoward events during an intensive care unit Mobility session and no cost difference (survivors + nonsurvivors) between the two arms, including Mobility Team costs. CONCLUSIONS: A Mobility Team using a mobility protocol initiated earlier physical therapy that was feasible, safe, did not increase costs, and was associated with decreased intensive care unit and hospital length of stay in survivors who received physical therapy during intensive care unit treatment compared with patients who received usual care.

Importance: Experimental data suggest that intravenous vitamin C may attenuate inflammation and vascular injury associated with sepsis and acute respiratory distress syndrome (ARDS). Objective: To determine the effect of intravenous vitamin C infusion on organ failure scores and biological markers of inflammation and vascular injury in patients with sepsis and ARDS. Design, Setting, and Participants: The CITRIS-ALI trial was a randomized, double-blind, placebo-controlled, multicenter trial conducted in 7 medical intensive care units in the United States, enrolling patients (N = 167) with sepsis and ARDS present for less than 24 hours. The study was conducted from September 2014 to November 2017, and final follow-up was January 2018. Interventions: Patients were randomly assigned to receive intravenous infusion of vitamin C (50 mg/kg in dextrose 5% in water, n = 84) or placebo (dextrose 5% in water only, n = 83) every 6 hours for 96 hours. Main Outcomes and Measures: The primary outcomes were change in organ failure as assessed by a modified Sequential Organ Failure Assessment score (range, 0-20, with higher scores indicating more dysfunction) from baseline to 96 hours, and plasma biomarkers of inflammation (C-reactive protein levels) and vascular injury (thrombomodulin levels) measured at 0, 48, 96, and 168 hours. Results: Among 167 randomized patients (mean [SD] age, 54.8 years [16.7]; 90 men [54%]), 103 (62%) completed the study to day 60. There were no significant differences between the vitamin C and placebo groups in the primary end points of change in mean modified Sequential Organ Failure Assessment score from baseline to 96 hours (from 9.8 to 6.8 in the vitamin C group [3 points] and from 10.3 to 6.8 in the placebo group [3.5 points]; difference, -0.10; 95% CI, -1.23 to 1.03; P = .86) or in C-reactive protein levels (54.1 vs 46.1 μg/mL; difference, 7.94 μg/mL; 95% CI, -8.2 to 24.11; P = .33) and thrombomodulin levels (14.5 vs 13.8 ng/mL; difference, 0.69 ng/mL; 95% CI, -2.8 to 4.2; P = .70) at 168 hours. Conclusions and Relevance: In this preliminary study of patients with sepsis and ARDS, a 96-hour infusion of vitamin C compared with placebo did not significantly improve organ dysfunction scores or alter markers of inflammation and vascular injury. Further research is needed to evaluate the potential role of vitamin C for other outcomes in sepsis and ARDS. Trial Registration: ClinicalTrials.gov Identifier: NCT02106975.