Statistical analysis plan with different statistical test if non-normal distribution

{
  "resourceType" : "Evidence",
  "id" : "example-statistic-model-include-if",
  "meta" : {
    "versionId" : "9",
    "lastUpdated" : "2025-03-10T14:59:32.227Z",
    "profile" : ["http://hl7.org/fhir/uv/ebm/StructureDefinition/statistic-model"]
  },
  "extension" : [{
    "url" : "http://hl7.org/fhir/StructureDefinition/structuredefinition-wg",
    "valueCode" : "cds"
  }],
  "url" : "https://fevir.net/resources/Evidence/346428",
  "identifier" : [{
    "type" : {
      "text" : "FEvIR Object Identifier"
    },
    "system" : "urn:ietf:rfc:3986",
    "value" : "https://fevir.net/FOI/346428",
    "assigner" : {
      "display" : "Computable Publishing LLC"
    }
  }],
  "title" : "Example of statistical analysis plan with different statistical test if non-normal distribution",
  "status" : "active",
  "author" : [{
    "name" : "Brian S. Alper, MD, MSPH"
  }],
  "publisher" : "HL7 International / Clinical Decision Support",
  "contact" : [{
    "telecom" : [{
      "system" : "url",
      "value" : "http://www.hl7.org/Special/committees/dss"
    }]
  }],
  "copyright" : "https://creativecommons.org/licenses/by-nc-sa/4.0/",
  "description" : "This example uses the StatisticModelIncludeIf extension to represent the model characteristic of Welch's 2-sample t-test if the data is consistent with a normal distribution (based on Shapiro-Wilk test with p-value >= 0.05) and a Wilcoxon Mann-Whitney test if not.",
  "variableDefinition" : [{
    "description" : "Adults with hypertension",
    "variableRole" : "population"
  },
  {
    "description" : "Reversitol vs. Placebo",
    "variableRole" : "exposure"
  },
  {
    "description" : "Change in systolic blood pressure from baseline to 3 months",
    "variableRole" : "outcome"
  }],
  "studyDesign" : [{
    "coding" : [{
      "system" : "https://fevir.net/sevco",
      "code" : "SEVCO:01003",
      "display" : "randomized assignment"
    }]
  }],
  "statistic" : [{
    "statisticType" : {
      "coding" : [{
        "system" : "https://fevir.net/sevco",
        "code" : "STATO:0000457",
        "display" : "difference in means"
      }]
    },
    "modelCharacteristic" : [{
      "extension" : [{
        "url" : "http://hl7.org/fhir/StructureDefinition/statistic-model-include-if",
        "extension" : [{
          "url" : "attribute",
          "valueCodeableConcept" : {
            "text" : "data distribution"
          }
        },
        {
          "url" : "value",
          "valueCodeableConcept" : {
            "text" : "normal distribution (Shapiro-Wilk test with p-value >= 0.05)"
          }
        }]
      }],
      "code" : {
        "text" : "Welch's 2-sample t-test"
      },
      "intended" : true
    },
    {
      "extension" : [{
        "url" : "http://hl7.org/fhir/StructureDefinition/statistic-model-include-if",
        "extension" : [{
          "url" : "attribute",
          "valueCodeableConcept" : {
            "text" : "data distribution"
          }
        },
        {
          "url" : "value",
          "valueCodeableConcept" : {
            "text" : "not consistent with normal distribution (Shapiro-Wilk test with p-value < 0.05)"
          }
        }]
      }],
      "code" : {
        "text" : "Wilcoxon Mann-Whitney test"
      },
      "intended" : true
    }]
  }]
}