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1899 2
1900 1
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1905 5
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1908 4
1909 4
1911 6
1912 6
1913 5
1914 4
1915 8
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1917 9
1918 5
1919 8
1920 8
1921 10
1922 6
1923 7
1924 4
1925 7
1926 4
1927 5
1928 9
1929 7
1930 8
1931 7
1932 2
1933 9
1934 3
1935 6
1936 4
1937 4
1938 7
1939 2
1941 4
1942 3
1943 4
1944 4
1945 3
1946 6
1947 6
1948 4
1949 8
1950 15
1951 8
1952 7
1953 16
1954 12
1955 19
1956 14
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1959 14
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1968 56
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1970 102
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1972 119
1973 110
1974 134
1975 1029
1976 1214
1977 1082
1978 1089
1979 1180
1980 1267
1981 1367
1982 1401
1983 1656
1984 1878
1985 1888
1986 1993
1987 2203
1988 2346
1989 3390
1990 3413
1991 3584
1992 3681
1993 3981
1994 4128
1995 4387
1996 4820
1997 4995
1998 5231
1999 5479
2000 6151
2001 6442
2002 6663
2003 7291
2004 7766
2005 8754
2006 9526
2007 10338
2008 10867
2009 11631
2010 12853
2011 14281
2012 15854
2013 16811
2014 18170
2015 18925
2016 19771
2017 20209
2018 21298
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475,499 results

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Page 1
Sample size estimation in diagnostic test studies of biomedical informatics.
Hajian-Tilaki K. Hajian-Tilaki K. J Biomed Inform. 2014 Apr;48:193-204. doi: 10.1016/j.jbi.2014.02.013. Epub 2014 Feb 26. J Biomed Inform. 2014. PMID: 24582925 Free article.
OBJECTIVES: This review provided a conceptual framework of sample size calculations in the studies of diagnostic test accuracy in various conditions and test outcomes. ...The results show how sample size is varied with accuracy index and effect size …
OBJECTIVES: This review provided a conceptual framework of sample size calculations in the studies of diagnostic test accuracy …
Sample size determination and power analysis using the G*Power software.
Kang H. Kang H. J Educ Eval Health Prof. 2021;18:17. doi: 10.3352/jeehp.2021.18.17. Epub 2021 Jul 30. J Educ Eval Health Prof. 2021. PMID: 34325496 Free PMC article. Review.
Appropriate sample size calculation and power analysis have become major issues in research and publication processes. ...This software is helpful for researchers to estimate the sample size and to conduct power analysis....
Appropriate sample size calculation and power analysis have become major issues in research and publication processes. ...This …
A brief overview of pilot studies and their sample size justification.
Kunselman AR. Kunselman AR. Fertil Steril. 2024 Jun;121(6):899-901. doi: 10.1016/j.fertnstert.2024.01.040. Epub 2024 Feb 6. Fertil Steril. 2024. PMID: 38331310 Free PMC article. Review.
In general, the answer is "no"; however, the sample size needs to be justified on the basis of the goal of the pilot study....
In general, the answer is "no"; however, the sample size needs to be justified on the basis of the goal of the pilot study....
Sample Size Estimation in Clinical Research: From Randomized Controlled Trials to Observational Studies.
Wang X, Ji X. Wang X, et al. Chest. 2020 Jul;158(1S):S12-S20. doi: 10.1016/j.chest.2020.03.010. Chest. 2020. PMID: 32658647 Review.
Sample size determination is an essential step in planning a clinical study. It is critical to understand that different study designs need different methods of sample size estimation. Although there is a vast literature discussing sample siz …
Sample size determination is an essential step in planning a clinical study. It is critical to understand that different study …
A simple formula for the calculation of sample size in pilot studies.
Viechtbauer W, Smits L, Kotz D, Budé L, Spigt M, Serroyen J, Crutzen R. Viechtbauer W, et al. J Clin Epidemiol. 2015 Nov;68(11):1375-9. doi: 10.1016/j.jclinepi.2015.04.014. Epub 2015 Jun 6. J Clin Epidemiol. 2015. PMID: 26146089
One of the goals of a pilot study is to identify unforeseen problems, such as ambiguous inclusion or exclusion criteria or misinterpretations of questionnaire items. Although sample size calculation methods for pilot studies have been proposed, none of them are dire …
One of the goals of a pilot study is to identify unforeseen problems, such as ambiguous inclusion or exclusion criteria or misinterpretation …
Estimating the sample size for a pilot randomised trial to minimise the overall trial sample size for the external pilot and main trial for a continuous outcome variable.
Whitehead AL, Julious SA, Cooper CL, Campbell MJ. Whitehead AL, et al. Stat Methods Med Res. 2016 Jun;25(3):1057-73. doi: 10.1177/0962280215588241. Epub 2015 Jun 19. Stat Methods Med Res. 2016. PMID: 26092476 Free PMC article.
Sample size justification is an important consideration when planning a clinical trial, not only for the main trial but also for any preliminary pilot trial. ...This paper looks at how we can choose an external pilot trial sample size in order to minim …
Sample size justification is an important consideration when planning a clinical trial, not only for the main trial but also f …
Sample size, power and effect size revisited: simplified and practical approaches in pre-clinical, clinical and laboratory studies.
Serdar CC, Cihan M, Yücel D, Serdar MA. Serdar CC, et al. Biochem Med (Zagreb). 2021 Feb 15;31(1):010502. doi: 10.11613/BM.2021.010502. Epub 2020 Dec 15. Biochem Med (Zagreb). 2021. PMID: 33380887 Free PMC article.
Calculating the sample size in scientific studies is one of the critical issues as regards the scientific contribution of the study. The sample size critically affects the hypothesis and the study design, and there is no straightforward way of calculat …
Calculating the sample size in scientific studies is one of the critical issues as regards the scientific contribution of the …
Characterising and justifying sample size sufficiency in interview-based studies: systematic analysis of qualitative health research over a 15-year period.
Vasileiou K, Barnett J, Thorpe S, Young T. Vasileiou K, et al. BMC Med Res Methodol. 2018 Nov 21;18(1):148. doi: 10.1186/s12874-018-0594-7. BMC Med Res Methodol. 2018. PMID: 30463515 Free PMC article.
BACKGROUND: Choosing a suitable sample size in qualitative research is an area of conceptual debate and practical uncertainty. That sample size principles, guidelines and tools have been developed to enable researchers to set, and justify the acceptabi …
BACKGROUND: Choosing a suitable sample size in qualitative research is an area of conceptual debate and practical uncertainty. …
Why is a small sample size not enough?
Cao Y, Chen RC, Katz AJ. Cao Y, et al. Oncologist. 2024 Sep 6;29(9):761-763. doi: 10.1093/oncolo/oyae162. Oncologist. 2024. PMID: 38934301 Free PMC article.
BACKGROUND: Clinical studies are often limited by resources available, which results in constraints on sample size. We use simulated data to illustrate study implications when the sample size is too small. METHODS AND RESULTS: Using 2 theoretical popul …
BACKGROUND: Clinical studies are often limited by resources available, which results in constraints on sample size. We use sim …
Practical guide to sample size calculations: non-inferiority and equivalence trials.
Flight L, Julious SA. Flight L, et al. Pharm Stat. 2016 Jan-Feb;15(1):80-9. doi: 10.1002/pst.1716. Epub 2015 Nov 25. Pharm Stat. 2016. PMID: 26604186 Free article.
A sample size justification is a vital part of any trial design. However, estimating the number of participants required to give a meaningful result is not always straightforward. A number of components are required to facilitate a suitable sample …
A sample size justification is a vital part of any trial design. However, estimating the number of participants require …
475,499 results
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