{
  "report_id": "055-active-base-continuity",
  "status": "validated",
  "version": "1.2",
  "publication": {
    "headline": "El 42 % de la base activa de final de año no había entrenado en el primer trimestre",
    "canonical_url": "https://wodbuster.com/observatorio/continuidad-base-activa/",
    "date_modified": "2026-07-18"
  },
  "period": {
    "first_quarter": "2025-01-01/2025-03-31",
    "last_quarter": "2025-10-01/2025-12-31"
  },
  "sample": {
    "tenants_attempted": 2174,
    "tenants_succeeded": 2174,
    "tenants_failed": 0,
    "eligible_centers": 1788,
    "q1_active_center_records": 377987,
    "q4_active_center_records": 401817,
    "active_in_both_center_records": 225424
  },
  "definitions": {
    "quarterly_active_participant": "Persona distinta con al menos una asistencia efectiva durante el trimestre en ese centro.",
    "observed_continuity": "Persona con asistencia efectiva tanto en el primer como en el último trimestre de 2025; no exige actividad en todos los meses intermedios.",
    "q4_not_active_in_q1": "Parte de la base activa del último trimestre sin asistencia efectiva observada durante el primero; puede incluir incorporaciones, regresos o personas que simplemente no entrenaron en Q1.",
    "active_base_change": "Variación entre el número de participantes activos de Q4 y Q1 dentro del mismo centro."
  },
  "findings": {
    "median_q4_not_active_q1_pct": 41.95,
    "median_q4_already_active_q1_pct": 58.05,
    "median_q1_seen_again_q4_pct": 61.01,
    "median_q4_vs_q1_active_change_pct": 4.38,
    "median_q1_q4_jaccard_pct": 41.87,
    "centers_q4_larger_pct": 61.19,
    "centers_q1_continuity_at_least_50_pct": 81.15
  },
  "series": {
    "continuity_by_community": [
      {"community":"Canarias","centers":105,"q4_not_active_q1_pct":44.44,"size_adjusted_difference_pp":2.25,"q1_seen_again_q4_pct":58.76,"q4_vs_q1_change_pct":3.50},
      {"community":"Comunidad de Madrid","centers":191,"q4_not_active_q1_pct":44.00,"size_adjusted_difference_pp":2.51,"q1_seen_again_q4_pct":59.42,"q4_vs_q1_change_pct":4.37},
      {"community":"Castilla y León","centers":37,"q4_not_active_q1_pct":43.55,"size_adjusted_difference_pp":0.46,"q1_seen_again_q4_pct":64.79,"q4_vs_q1_change_pct":5.38},
      {"community":"Región de Murcia","centers":82,"q4_not_active_q1_pct":43.23,"size_adjusted_difference_pp":1.81,"q1_seen_again_q4_pct":60.32,"q4_vs_q1_change_pct":5.59},
      {"community":"Comunidad Valenciana","centers":291,"q4_not_active_q1_pct":43.03,"size_adjusted_difference_pp":1.25,"q1_seen_again_q4_pct":60.00,"q4_vs_q1_change_pct":5.63},
      {"community":"Andalucía","centers":618,"q4_not_active_q1_pct":42.31,"size_adjusted_difference_pp":0.25,"q1_seen_again_q4_pct":59.94,"q4_vs_q1_change_pct":3.75},
      {"community":"Islas Baleares","centers":65,"q4_not_active_q1_pct":39.86,"size_adjusted_difference_pp":-2.63,"q1_seen_again_q4_pct":65.15,"q4_vs_q1_change_pct":8.38},
      {"community":"Galicia","centers":48,"q4_not_active_q1_pct":39.13,"size_adjusted_difference_pp":-3.21,"q1_seen_again_q4_pct":64.19,"q4_vs_q1_change_pct":6.32},
      {"community":"País Vasco","centers":31,"q4_not_active_q1_pct":39.04,"size_adjusted_difference_pp":-2.50,"q1_seen_again_q4_pct":60.24,"q4_vs_q1_change_pct":-1.18},
      {"community":"Castilla-La Mancha","centers":87,"q4_not_active_q1_pct":38.39,"size_adjusted_difference_pp":-3.59,"q1_seen_again_q4_pct":65.22,"q4_vs_q1_change_pct":3.92},
      {"community":"Cataluña","centers":98,"q4_not_active_q1_pct":38.36,"size_adjusted_difference_pp":-3.18,"q1_seen_again_q4_pct":61.96,"q4_vs_q1_change_pct":3.07}
    ],
    "continuity_by_center_size": [
      {"size_band":"Menos de 75","centers":107,"median_typical_active":64.0,"q4_not_active_q1_pct":41.10,"q1_seen_again_q4_pct":56.52,"q4_vs_q1_change_pct":0.00,"jaccard_pct":40.38,"centers_q4_larger_pct":48.60},
      {"size_band":"De 75 a 149","centers":566,"median_typical_active":115.0,"q4_not_active_q1_pct":43.09,"q1_seen_again_q4_pct":60.35,"q4_vs_q1_change_pct":5.48,"jaccard_pct":40.59,"centers_q4_larger_pct":60.78},
      {"size_band":"De 150 a 299","centers":747,"median_typical_active":208.0,"q4_not_active_q1_pct":41.55,"q1_seen_again_q4_pct":61.17,"q4_vs_q1_change_pct":4.13,"jaccard_pct":42.28,"centers_q4_larger_pct":61.45},
      {"size_band":"300 o más","centers":368,"median_typical_active":380.0,"q4_not_active_q1_pct":41.62,"q1_seen_again_q4_pct":61.88,"q4_vs_q1_change_pct":4.68,"jaccard_pct":42.43,"centers_q4_larger_pct":64.95}
    ],
    "center_percentiles": [
      {"metric":"Base de Q4 no activa en Q1","p25":35.29,"median":41.95,"p75":50.92},
      {"metric":"Base de Q4 ya activa en Q1","p25":49.08,"median":58.05,"p75":64.71},
      {"metric":"Base de Q1 observada también en Q4","p25":52.63,"median":61.01,"p75":67.8},
      {"metric":"Variación del tamaño activo Q4 frente a Q1","p25":-5.17,"median":4.38,"p75":16.4},
      {"metric":"Similitud entre ambas bases","p25":34.12,"median":41.87,"p75":48.47}
    ],
    "threshold_sensitivity": [
      {"minimum_active_per_quarter":30,"eligible_centers":1892,"q4_not_active_q1_pct":42.2,"q4_vs_q1_change_pct":4.47,"q1_seen_again_q4_pct":60.8},
      {"minimum_active_per_quarter":50,"eligible_centers":1788,"q4_not_active_q1_pct":41.95,"q4_vs_q1_change_pct":4.38,"q1_seen_again_q4_pct":61.01},
      {"minimum_active_per_quarter":100,"eligible_centers":1442,"q4_not_active_q1_pct":41.41,"q4_vs_q1_change_pct":4.16,"q1_seen_again_q4_pct":61.46}
    ]
  },
  "quality": {
    "minimum_active_participants_per_quarter": 50,
    "all_source_queries_return_only_three_counts": true,
    "failed_centers": 0
  },
  "privacy": {
    "personal_identifiers_extracted": false,
    "center_identifiers_exported": false,
    "minimum_centers_in_public_result": 1442
  },
  "limitations": [
    "La unidad es asistencia observada, no contrato, cuota o alta comercial.",
    "No estar activo en Q1 no significa necesariamente ser nuevo en Q4: puede tratarse de una persona que regresa o que no entrenó durante el primer trimestre.",
    "Aparecer en Q1 y Q4 no demuestra continuidad durante todos los meses intermedios.",
    "La comparación utiliza dos estaciones distintas del mismo año y no separa estacionalidad de cambios estructurales.",
    "La muestra representa centros usuarios de WodBuster y no todo el mercado español."
  ]
}