Power calculation in multiply imputed data

Zha, Ruochen; Harel, Ofer

doi:10.1007/s00362-019-01098-8

Cited by 11 publications

(12 citation statements)

References 30 publications

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“…Multiple imputations were used to handle missing data (see Table 1 for percentages of missing data per variable) to ensure sufficient statistical power ( Zha & Harel, 2021 ). We assumed missing data to be completely at random, which was supported by a non-significant Little's MCAR Test, χ 2 (99) = 108.00, p = .258.…”

Section: Resultsmentioning

confidence: 99%

“…Thus, sample size was not planned to be sufficiently powered for the current analyses. Since power analyses for multiple imputed data and single regression coefficients are not yet well established ( Zha & Harel, 2021 ), we based our post-hoc power analysis on complete cases ( n = 80) and calculated the statistical power ( α = .05) to detect an at least small effect ( d = .20, Cohen (1992) ) of agency, communion, physical or emotional health on SPA ongoing development or SPA physical losses. Results indicate that analyses based on complete data would have been sufficiently powered, β – 1 = .80.…”

Section: Resultsmentioning

confidence: 99%

“…Results indicate that analyses based on complete data would have been sufficiently powered, β – 1 = .80. Thus, based on simulation studies ( Kontopantelis et al, 2017 ; Zha & Harel, 2021 ), it is plausible to assume that the achieved power using multiple imputations is considerably higher and that our analyses are sufficiently powered.…”

Section: Resultsmentioning

confidence: 99%

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Associations of Agency and Communion With Domain-Specific Self-Perceptions of Aging: A Cross-Sectional Study In Old-Old Adults in Poor Health

Blawert

Schäfer

Wurm

2021

Int J Aging Hum Dev

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A large body of research indicates that self-perceptions of aging (SPA) play an important role for health in later life. Hence, more research on SPA and correlates is needed, especially in old age and poor health, where negative SPA tend to prevail. Recent studies identified personality as an important correlate of SPA in young-old and relatively healthy samples. Thus, we investigated cross-sectional associations of agency and communion with two SPA domains in a sample of old-old adults in poor health ( n = 154; Mage = 81.55, SD = 4.56, 58.4% women). In multiple regression analyses, agency and communion were associated with SPA related to ongoing development beyond health. In contrast, only health as a covariate was significantly associated with SPA related to physical losses. Thus, personality may be a resource associated with gain-related SPA, at least for those in poor health and old age.

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Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

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Associations of Agency and Communion With Domain-Specific Self-Perceptions of Aging: A Cross-Sectional Study In Old-Old Adults in Poor Health

Blawert

Schäfer

Wurm

2021

Int J Aging Hum Dev

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“…In practice we might expect missing data to be addressed through multiple imputation methods, which would typically lead to more power than the assumed complete case approach. A potential extension of the methods proposed could formally model the effect of multiple imputation on power 27 and incorporate this when defining pilot trial hypotheses.…”

Section: Discussionmentioning

confidence: 99%

A hypothesis test of feasibility for external pilot trials assessing recruitment, follow‐up, and adherence rates

Wilson

Farrin

Walwyn

2021

Statistics in Medicine

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The power of a large clinical trial can be adversely affected by low recruitment, follow‐up, and adherence rates. External pilot trials estimate these rates and use them, via prespecified decision rules, to determine if the definitive trial is feasible and should go ahead. There is little methodological research underpinning how these decision rules, or the sample size of the pilot, should be chosen. In this article we propose a hypothesis test of the feasibility of a definitive trial, to be applied to the external pilot data and used to make progression decisions. We quantify feasibility by the power of the planned trial, as a function of recruitment, follow‐up, and adherence rates. We use this measure to define hypotheses to test in the pilot, propose a test statistic, and show how the error rates of this test can be calculated for the common scenario of a two‐arm parallel group definitive trial with a single normally distributed primary endpoint. We use our method to redesign TIGA‐CUB, an external pilot trial comparing a psychotherapy with treatment as usual for children with conduct disorders. We then extend our formulation to include using the pilot data to estimate the standard deviation of the primary endpoint and incorporate this into the progression decision.

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“…Although we applied ITT with the imputation of missing values and thus reached the calculated sample size of 25 participants per group, there is some evidence that we lost power compared with the calculation of a full dataset. 75 3) Unlike pharmaceutic agents, exercise is a comprehensive tool which, if properly designed and applied, might positively address a large variety of biomedical variables. Thus, it is challenging to design and evaluate exercise protocols that aimed to address several aims important for health and performance.…”

Section: Dovepressmentioning

confidence: 99%

Changes in Menopausal Risk Factors in Early Postmenopausal Osteopenic Women After 13 Months of High-Intensity Exercise: The Randomized Controlled ACTLIFE-RCT

Hettchen¹,

Stengel²,

Kohl³

et al. 2021

CIA

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The menopausal transition is a critical period in women's lives. Exercise might be the most promising non-pharmaceutic intervention to address the large variety of risk factors related to the pronounced estradiol decline during peri-and early-postmenopause. The aim of this study was to determine the effect of an 18-month multipurpose exercise program on risk factors and symptoms related to the menopausal transition. Fifty-four women 1-5 years postmenopause with osteopenia or osteoporosis were randomly assigned 1) to a high impact weight-bearing/high-intensity/velocity resistance training group (EG: n=27) exercising three times a week or 2) to an attendance control group (CG: n=27) that performed low-intensity exercise once a week. Both groups were supplemented with cholecalciferol and calcium. The primary study endpoint was bone mineral density (BMD) at lumbar spine (LS) and total hip, secondary outcomes were lean body mass (LBM), total and abdominal body percentage, metabolic syndrome Z-Score (MetS-Z), menopausal symptoms and muscle strength and power. Due to COVID-19, the study was stopped after 13 months. We observed significant effects for BMD-LS (EG: 0.002±.018 versus CG: −.009±0.018 mg/cm2, p=0.027) but not for BMD total hip (EG: −0.01±.016 versus CG: −.009±0.020 mg/cm2, p=0.129). LBM improved significantly in the EG and decreased in the CG (0.39±1.08 vs −0.37±1.34 kg, p=0.026). Total and abdominal body fat improved significantly in the EG and was maintained in the CG (−1.44±1.49 vs −0.02±1.55 kg, p=0.002 and-1.50±2.33 vs 0.08±2.07 kg, p=0.011). Significant effects in favor of the EG were also determined for menopausal symptoms (p=0.029), hip/leg extension strength (p<0.001) and power (p<0.001). However, changes of the MetS-Z did not differ significantly (p=0.149) between EG and CG. In summary, with minor exceptions, we demonstrated the effectiveness of a multipurpose exercise protocol dedicated to early-postmenopausal women on various risk factors and complaints related to the menopausal transition.

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Power calculation in multiply imputed data

Cited by 11 publications

References 30 publications

Associations of Agency and Communion With Domain-Specific Self-Perceptions of Aging: A Cross-Sectional Study In Old-Old Adults in Poor Health

Associations of Agency and Communion With Domain-Specific Self-Perceptions of Aging: A Cross-Sectional Study In Old-Old Adults in Poor Health

A hypothesis test of feasibility for external pilot trials assessing recruitment, follow‐up, and adherence rates

Changes in Menopausal Risk Factors in Early Postmenopausal Osteopenic Women After 13 Months of High-Intensity Exercise: The Randomized Controlled ACTLIFE-RCT

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