{
  "abstract": "Pilot trials have a key role in preparing for definitive randomized trials, yet determining their sample size remains a common challenge. This article provides practical guidance, methods, and tools—including step-by-step examples, sample size tables, and statistical code—for calculating and justifying sample sizes in external randomized pilot trials.",
  "authors": [
    {
      "affiliations": [
        "Department of Epidemiology, University of North Carolina Gillings School of Global Public Health, Chapel Hill, NC 27599, USA"
      ],
      "name": "Xiangji Ying"
    },
    {
      "affiliations": [
        "Department of Psychiatry, Washington University School of Medicine, St Louis, MO, USA"
      ],
      "name": "Kenneth E Freedland"
    },
    {
      "affiliations": [
        "Department of Family and Preventive Medicine, Rush University Medical Center, Chicago, IL, USA"
      ],
      "name": "Lynda H Powell"
    },
    {
      "affiliations": [
        "Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, MA, USA"
      ],
      "name": "Elizabeth A Stuart"
    },
    {
      "affiliations": [
        "Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MA, USA"
      ],
      "name": "Stephan Ehrhardt"
    },
    {
      "affiliations": [
        "Department of Epidemiology, University of North Carolina Gillings School of Global Public Health, Chapel Hill, NC 27599, USA"
      ],
      "name": "Evan Mayo-Wilson"
    }
  ],
  "title": "Determining sample size for pilot trials: a tutorial",
  "uid": "3596def2-da41-56b0-bd95-9050413a6122"
}