{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,3]],"date-time":"2026-10-03T03:51:25Z","timestamp":1790999485934,"version":"4.1.0"},"reference-count":3,"publisher":"Wiley","issue":"8","license":[{"start":{"date-parts":[[2007,1,22]],"date-time":"2007-01-22T00:00:00Z","timestamp":1169424000000},"content-version":"vor","delay-in-days":5500,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Statistics in Medicine"],"published-print":{"date-parts":[[1992,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>\n                    I suggest for memorization an equation for calculating approximate sample size requirements intended only for a specific set of values (80 per cent power for a two\u2010tailed alpha = 0.05 test) which seems to occur often in biopharmaceutical research. After presenting the formula in terms of variance estimate\n                    <jats:italic>s<\/jats:italic>\n                    <jats:sup>2<\/jats:sup>\n                    and effect size\n                    <jats:italic>d<\/jats:italic>\n                    , I derive a few alternative forms and then discuss the accuracy of the approximation and other properties as well as examples of its use.\n                  <\/jats:p>","DOI":"10.1002\/sim.4780110811","type":"journal-article","created":{"date-parts":[[2007,4,27]],"date-time":"2007-04-27T07:21:36Z","timestamp":1177658496000},"page":"1099-1102","source":"Crossref","is-referenced-by-count":222,"title":["Sixteen\n                    <i>S<\/i>\n                    \u2010squared over\n                    <i>D<\/i>\n                    \u2010squared: A relation for crude sample size estimates"],"prefix":"10.1002","volume":"11","author":[{"given":"Robert","family":"Lehr","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2007,1,22]]},"reference":[{"key":"e_1_2_1_2_2","volume-title":"Statistical Methods for Rates and Proportions","author":"Fleiss J. L.","year":"1981"},{"key":"e_1_2_1_3_2","volume-title":"Statistical Methods","author":"Snedecor G. W.","year":"1980"},{"key":"e_1_2_1_4_2","volume-title":"Statistical Methods for the Analysis of Biomedical Data","author":"Woolson R. F.","year":"1987"}],"container-title":["Statistics in Medicine"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/api.wiley.com\/onlinelibrary\/tdm\/v1\/articles\/10.1002%2Fsim.4780110811","content-type":"unspecified","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/sim.4780110811","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,10,23]],"date-time":"2023-10-23T17:08:39Z","timestamp":1698080919000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1002\/sim.4780110811"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1992,1]]},"references-count":3,"journal-issue":{"issue":"8","published-print":{"date-parts":[[1992,1]]}},"alternative-id":["10.1002\/sim.4780110811"],"URL":"https:\/\/doi.org\/10.1002\/sim.4780110811","archive":["Portico"],"relation":{},"ISSN":["0277-6715","1097-0258"],"issn-type":[{"value":"0277-6715","type":"print"},{"value":"1097-0258","type":"electronic"}],"subject":[],"published":{"date-parts":[[1992,1]]}}}