{
  "status_code": 200,
  "request": {
    "model": "gpt-5-mini",
    "fields": [
      {
        "name": "country",
        "description": "Country or countries where the study population was recruited or data originates. Use standard country names.",
        "data_type_primary": "array-string",
        "examples": [
          "United Kingdom",
          "United States",
          "Denmark",
          "International"
        ],
        "examples_mode": "guide",
        "depth": "minimal"
      },
      {
        "name": "study_size",
        "description": "Total number of participants in the analysed cohort as a numeric value if explicitly stated; null if absent.",
        "data_type_primary": "number",
        "examples": [
          "32091",
          "1263"
        ],
        "examples_mode": "guide",
        "depth": "minimal"
      },
      {
        "name": "year_coverage",
        "description": "Decade bins covering the study data collection period. Select all applicable ranges.",
        "data_type_primary": "array-string",
        "examples": [
          "1980-1989",
          "1990-1999",
          "2000-2009",
          "2010-2019",
          "2020-2029"
        ],
        "examples_mode": "enum",
        "depth": "minimal"
      },
      {
        "name": "gender",
        "description": "Sex distribution of the study population.",
        "data_type_primary": "string",
        "examples": [
          "Both",
          "Male",
          "Female",
          "Not Applicable"
        ],
        "examples_mode": "enum",
        "depth": "minimal"
      },
      {
        "name": "age",
        "description": "Age categories of the study population. Select all applicable bins based on stated age range or mean/median age.",
        "data_type_primary": "array-string",
        "examples": [
          "<45",
          "45-65",
          "65+"
        ],
        "examples_mode": "enum",
        "depth": "minimal"
      },
      {
        "name": "publication_type",
        "description": "Study design or publication type explicitly stated.",
        "data_type_primary": "string",
        "examples": [
          "Prospective cohort study",
          "Retrospective cohort study",
          "Meta-analysis",
          "Randomized controlled trial",
          "Cross-sectional study",
          "Systematic review"
        ],
        "examples_mode": "enum",
        "depth": "minimal"
      },
      {
        "name": "model_type",
        "description": "Statistical or analytical modelling approaches used.",
        "data_type_primary": "array-string",
        "examples": [
          "Cox proportional hazards model",
          "Logistic regression",
          "Random-effect meta-analysis",
          "Poisson regression"
        ],
        "examples_mode": "guide",
        "depth": "minimal"
      },
      {
        "name": "data_source",
        "description": "Dataset, registry, cohort, or database from which study data were obtained.",
        "data_type_primary": "array-string",
        "examples": [
          "UK Biobank",
          "NHANES",
          "Clinical Practice Research Datalink"
        ],
        "examples_mode": "guide",
        "depth": "minimal"
      },
      {
        "name": "subpopulation",
        "description": "Specific subgroups or eligibility criteria analysed within the study.",
        "data_type_primary": "array-string",
        "examples": [
          "General population",
          "Smokers",
          "COPD",
          "Lung Cancer",
          "Hypertensive subjects"
        ],
        "examples_mode": "guide",
        "depth": "minimal"
      },
      {
        "name": "age_exact",
        "description": "Exact reported age summary statistic when available (e.g. mean, median with SD/IQR); null if absent.",
        "data_type_primary": "string",
        "examples": [
          "59.7 (11.9)",
          "~55",
          "68.9 (12.8)"
        ],
        "examples_mode": "guide",
        "depth": "minimal"
      },
      {
        "name": "follow_up_years",
        "description": "Duration of participant follow-up in predefined year ranges. Select all applicable bins.",
        "data_type_primary": "array-string",
        "examples": [
          "<5",
          "5-9",
          "10-19",
          "20+"
        ],
        "examples_mode": "enum",
        "depth": "minimal"
      }
    ],
    "record_count": 20
  },
  "response": {
    "estimated_input_tokens": 11600,
    "estimated_output_tokens": 5500,
    "estimated_cost_usd": 0.01332,
    "confidence": "approximate",
    "disclaimer": "Estimate based on empirical averages. Actual cost may vary +-30% depending on abstract length and field complexity."
  }
}