| Title |
Sample size requirements for case-control study designs
|
|---|---|
| Published in |
BMC Medical Research Methodology, November 2001
|
| DOI | 10.1186/1471-2288-1-11 |
| Pubmed ID | |
| Authors |
Michael D Edwardes |
| Abstract |
Published formulas for case-control designs provide sample sizes required to determine that a given disease-exposure odds ratio is significantly different from one, adjusting for a potential confounder and possible interaction. The formulas are extended from one control per case to F controls per case and adjusted for a potential multi-category confounder in unmatched or matched designs. Interactive FORTRAN programs are described which compute the formulas. The effect of potential disease-exposure-confounder interaction may be explored. Software is now available for computing adjusted sample sizes for case-control designs. |
Mendeley readers
The data shown below were compiled from readership statistics for 200 Mendeley readers of this research output. Click here to see the associated Mendeley record.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| Nigeria | 3 | 2% |
| United States | 3 | 2% |
| Zimbabwe | 1 | <1% |
| Malawi | 1 | <1% |
| Tanzania, United Republic of | 1 | <1% |
| United Kingdom | 1 | <1% |
| Germany | 1 | <1% |
| Uzbekistan | 1 | <1% |
| Australia | 1 | <1% |
| Other | 0 | 0% |
| Unknown | 187 | 94% |
Demographic breakdown
| Readers by professional status | Count | As % |
|---|---|---|
| Student > Master | 39 | 20% |
| Researcher | 36 | 18% |
| Student > Ph. D. Student | 27 | 14% |
| Student > Doctoral Student | 11 | 6% |
| Student > Bachelor | 11 | 6% |
| Other | 44 | 22% |
| Unknown | 32 | 16% |
| Readers by discipline | Count | As % |
|---|---|---|
| Medicine and Dentistry | 81 | 41% |
| Nursing and Health Professions | 22 | 11% |
| Agricultural and Biological Sciences | 12 | 6% |
| Mathematics | 7 | 4% |
| Environmental Science | 6 | 3% |
| Other | 33 | 17% |
| Unknown | 39 | 20% |
Attention Score in Context
This research output has an Altmetric Attention Score of 3. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 18 August 2011.
All research outputs
#13,042,273
of 22,977,819 outputs
Outputs from BMC Medical Research Methodology
#1,198
of 2,028 outputs
Outputs of similar age
#100,615
of 122,594 outputs
Outputs of similar age from BMC Medical Research Methodology
#2
of 3 outputs
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