Hip Pelvis.  2018 Mar;30(1):1-4. 10.5371/hp.2018.30.1.1.

How to Increase Your “Power”

• Kim J

• KMID: 2408178
• DOI: http://doi.org/10.5371/hp.2018.30.1.1

Abstract

No abstract available.

MeSH Terms

Data Accuracy
Data Interpretation, Statistical
Statistics as Topic
Biomedical Research
Analysis of Variance

Figure

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  Fig. 1 A 2 by 2 contingency table showing a cure rate of 20% and a cure rate of 10% for each group with 100 people respectively.

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  Fig. 2 The increase of the number doesn't make any change in odds ratio (OR), but make the 95% confidence interval (CI) narrower and statistically significant.

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  Fig. 3 The ideal situation with sensitivity and specificity in the value of 100% and the real situation with sensitivity and specificity in the value of 90%.

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  Fig. 4 The result of the increase of number of samples and the increase of sensitivity and specificity. OR: odds ratio, CI: confidence interval.

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  Fig. 5 The summarized chart of the number of samples (N means number of one group) and the sensitivity and specificity in the view of odds ratio (OR) and its 95% confidence interval (CI).

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  Fig. 6 The effect of mixed population with increased number. OR: odds ratio, CI: confidence interval.

Reference

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