var fDesc=new Array(); fDesc[0] = "Statistical power analysis and sample size determination are crucial elements of study design. A study that is too small may produce inconclusive results, while a study that is too large will waste scarce resources. nTerim provides power and sample size calculations for group sequential trials. nTerim uses the alpha-spending function of Lan & DeMets and includes the spending functions from O’Brien-Fleming, Pocock, Hwang-Shih-DeCani and others."; function tShowHide(id, show) { var s = document.getElementById("desc"); if ((s.innerHTML.length<=212 || show==1) && show!=2) { s.innerHTML = fDesc[id]; if (document.getElementById('m1')) document.getElementById('m1').style.display='none'; if (document.getElementById('m2')) document.getElementById('m2').style.display='none'; if (document.getElementById('more_txt')) document.getElementById('more_txt').style.display='inline'; } else { s.innerHTML = ''; } }