Ideal weight: drop Broca family and Hamwi

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

app/lib/services/body_calc.dart

@@ -41,11 +41,6 @@ const String trefethenNote =
     "Trefethen's new BMI = 1.3 x kg / m^2.5: corrects classic BMI, which "
     'over-reads tall people and under-reads short ones.';
 
-/// Broca explained, shown under the ideal-weight list.
-const String brocaNote =
-    'Broca = height in cm - 100 (1871); it overshoots, so Broca (modified) '
-    'takes 10% off it for men and 15% for women.';
-
 /// The lean-mass formula the calorie table switches to with a body fat %.
 const String katchMcArdle = 'Katch-McArdle';
 
@@ -150,8 +145,9 @@ double? _perInch(
 
 /// Every ideal-body-weight formula we can evaluate, in kg.
 ///
-/// Only Creff uses age. The BMI healthy range is [healthyRange], shown with
+/// Only data-backed ones (Devine, its MetLife refits, Peterson); Broca, its
-/// BMI; [idealSummary] averages these.
+/// derivatives and Hamwi were dropped. The BMI healthy range is
+/// [healthyRange], shown with BMI; [idealSummary] averages these.
 List<Formula> idealWeights(Biometrics bio) {
   final h = bio.heightCm;
   final inches = h / _cmPerInch - _fiveFeetIn;
@@ -168,14 +164,6 @@ List<Formula> idealWeights(Biometrics bio) {
       'Miller',
       _perInch(inches, male ? 56.2 : 53.1, male ? 1.41 : 1.36, defined: ok),
     ),
-    Formula(
-      'Hamwi',
-      _perInch(inches, male ? 48 : 45.5, male ? 2.7 : 2.2, defined: ok),
-    ),
-    Formula('Broca', h - 100.0),
-    Formula('Broca (modified)', (h - 100.0) * (male ? 0.9 : 0.85)),
-    Formula('Lorentz', h - 100.0 - (h - 150.0) / (male ? 4.0 : 2.0)),
-    Formula('Creff (age)', (h - 100.0 + bio.ageYears / 10.0) * 0.9),
     Formula(
       'Peterson (BMI 22)',
       2.2 * _targetBmi + 3.5 * _targetBmi * (metres - 1.5),

app/lib/widgets/body/body_stats_cards.dart

@@ -66,10 +66,9 @@ class IdealWeightCard extends StatelessWidget {
             '${oneDecimal(summary.$2)}-${oneDecimal(summary.$3)} kg',
           ),
         ],
-        const BodyNote(brocaNote),
         if (undefined)
           const BodyNote(
-            'Devine, Robinson, Miller and Hamwi are undefined below 152.4 cm.',
+            'Devine, Robinson and Miller are undefined below 152.4 cm.',
           ),
       ],
     );

app/pubspec.yaml

@@ -2,7 +2,7 @@ name: diet_guard_app
 description: "Companion phone app for diet_guard: log meals on the go."
 publish_to: 'none'
 
-version: 1.0.122+1
+version: 1.0.123+1
 
 environment:
   sdk: ^3.12.2

app/test/screens/body_screen_test.dart

@@ -71,7 +71,7 @@ void main() {
     expect(find.text('24.7'), findsOneWidget);
     expect(find.text('59.9-80.7 kg'), findsOneWidget);
     expect(find.text('Average of all'), findsOneWidget);
-    expect(find.textContaining('Broca = height'), findsOneWidget);
+    expect(find.textContaining('Broca'), findsNothing);
     expect(find.text('1780 kcal'), findsOneWidget);
     expect(find.text('n/a -- log a body-fat %'), findsNWidgets(2));
     // 5000 steps over baseline x 0.747 m x 0.5 x 80 kg = 149.4 kcal, and

app/test/widgets/body/body_widgets_test.dart

@@ -77,7 +77,7 @@ void main() {
         children: [BmiCard(bio: _short), IdealWeightCard(bio: _short)],
       ),
     );
-    expect(find.text('n/a'), findsNWidgets(4));
+    expect(find.text('n/a'), findsNWidgets(3));
     expect(find.textContaining('undefined below 152.4 cm'), findsOneWidget);
     expect(find.text('adult categories do not apply under 20'), findsOneWidget);
   });

diet_guard/_body_calc.py

@@ -23,7 +23,6 @@ from diet_guard._budget_biometrics import Biometrics, mifflin_st_jeor_bmr
 
 __all__ = [
     "BMI_PRIME_NOTE",
-    "BROCA_NOTE",
     "KATCH_MCARDLE",
     "TREFETHEN_NOTE",
     "BmiReport",
@@ -38,7 +37,7 @@ __all__ = [
 ]
 
 _CM_PER_INCH = 2.54
-# The inch-based formulas (Devine, Robinson, Miller, Hamwi) are all
+# The inch-based formulas (Devine, Robinson, Miller) are all
 # "base + k per inch over five feet"; below five feet they are undefined.
 _FIVE_FEET_IN = 60.0
 # Adult BMI categories are WHO's and do not apply to anyone still growing.
@@ -71,10 +70,6 @@ TREFETHEN_NOTE = (
     "over-reads tall people and under-reads short ones."
 )
 KATCH_MCARDLE = "Katch-McArdle"
-BROCA_NOTE = (
-    "Broca = height in cm - 100 (1871); it overshoots, so Broca (modified) "
-    "takes 10% off it for men and 15% for women."
-)
 
 
 def half_up(value: float, digits: int = 0) -> float:
@@ -140,9 +135,11 @@ def _per_inch(
 def ideal_weights(bio: Biometrics) -> tuple[Formula, ...]:
     """Every ideal-body-weight formula we can evaluate, in kg.
 
-    Only Creff uses age -- it is the one that answers "ideal weight for my age
+    Only data-backed ones: Devine and its MetLife-table refits (Robinson,
-    and height". The BMI healthy range is :func:`healthy_range`, shown with
+    Miller), and Peterson (NHANES). Broca, its derivatives (modified Broca,
-    BMI rather than here; :func:`ideal_summary` averages these.
+    Lorentz, Creff) and Hamwi were dropped as unvalidated rules of thumb.
+    The BMI healthy range is :func:`healthy_range`, shown with BMI rather than
+    here; :func:`ideal_summary` averages these.
     """
     h = bio.height_cm
     inches = h / _CM_PER_INCH - _FIVE_FEET_IN
@@ -161,14 +158,6 @@ def ideal_weights(bio: Biometrics) -> tuple[Formula, ...]:
                 inches, 56.2 if male else 53.1, 1.41 if male else 1.36, defined=ok
             ),
         ),
-        Formula(
-            "Hamwi",
-            _per_inch(inches, 48.0 if male else 45.5, 2.7 if male else 2.2, defined=ok),
-        ),
-        Formula("Broca", h - 100.0),
-        Formula("Broca (modified)", (h - 100.0) * (0.9 if male else 0.85)),
-        Formula("Lorentz", h - 100.0 - (h - 150.0) / (4.0 if male else 2.0)),
-        Formula("Creff (age)", (h - 100.0 + bio.age_years / 10.0) * 0.9),
         Formula(
             "Peterson (BMI 22)", 2.2 * _TARGET_BMI + 3.5 * _TARGET_BMI * (metres - 1.5)
         ),

diet_guard/_body_report.py

@@ -16,7 +16,7 @@ from diet_guard._activity_kcal import (
     METHODS_NOTE,
     session_kcal,
 )
-from diet_guard._body_calc import BMI_PRIME_NOTE, BROCA_NOTE, TREFETHEN_NOTE, half_up
+from diet_guard._body_calc import BMI_PRIME_NOTE, TREFETHEN_NOTE, half_up
 from diet_guard._body_energy import KCAL_PER_KG, MIN_TARGET_KCAL, activity_label
 from diet_guard._body_steps import STEP_BASELINE
 from diet_guard._body_store import age_on
@@ -114,7 +114,6 @@ def ideal_lines(view: BodyView) -> list[str]:
         avg, low, high = summary
         lines.append(f"  {'Average of all':<{_NAME_W}}{_num(avg, 1)} kg")
         lines.append(f"  {'Ideal range':<{_NAME_W}}{_num(low, 1)}-{_num(high, 1)} kg")
-    lines.extend(_wrap(BROCA_NOTE, "  "))
     return lines
 
 

diet_guard/tests/test_body_calc.py

@@ -18,6 +18,7 @@ from diet_guard._body_calc import (
     bmr_formulas,
     half_up,
     ideal_summary,
+    ideal_weights,
     table_bmr,
 )
 from diet_guard._body_energy import (
@@ -81,6 +82,11 @@ class TestBmr:
     def test_ideal_summary_is_none_when_nothing_applies(self) -> None:
         assert ideal_summary(()) is None
 
+    def test_only_data_backed_ideal_weight_formulas(self) -> None:
+        # Broca, its derivatives and Hamwi are unvalidated rules of thumb.
+        names = tuple(f.name for f in ideal_weights(_MAN))
+        assert names == ("Devine", "Robinson", "Miller", "Peterson (BMI 22)")
+
 
 class TestGoal:
     def test_kg_per_day_signs(self) -> None:

docs/DOCS-body.md

@@ -115,8 +115,8 @@ every formula's daily total. Heart-rate input was dropped at the user's call.
 ## Calculations (`_body_calc.py`, `_body_energy.py`, `_week_plan.py`)
 
 - **BMI** kg/m², BMI Prime, Trefethen; WHO bands, not applied under 20.
-- **Ideal weight**: Devine, Robinson, Miller, Hamwi (undefined < 152.4 cm),
+- **Ideal weight**: Devine, Robinson, Miller (undefined < 152.4 cm), Peterson;
-  Broca, modified Broca, Lorentz, Creff (the one that uses age), Peterson;
+  Broca, modified Broca, Lorentz, Creff and Hamwi were dropped (unvalidated);
   then their average and min-max "ideal range". The BMI 18.5-24.9 healthy
   range sits with BMI.
 - **BMR**: Mifflin-St Jeor, Harris-Benedict (1984), and with a body fat

tests/fixtures/body_calc.json

@@ -27,26 +27,6 @@
      "Miller",
      71.5212598425197
     ],
-    [
-     "Hamwi",
-     77.33858267716536
-    ],
-    [
-     "Broca",
-     80.0
-    ],
-    [
-     "Broca (modified)",
-     72.0
-    ],
-    [
-     "Lorentz",
-     72.5
-    ],
-    [
-     "Creff (age)",
-     74.7
-    ],
     [
      "Peterson (BMI 22)",
      71.50000000000001
@@ -90,9 +70,9 @@
     ]
    ],
    "ideal_summary": [
-    74.13307086614174,
+    72.66476377952756,
     71.50000000000001,
-    80.0
+    74.99212598425197
    ],
    "healthy_range": [
     59.94000000000001,
@@ -361,26 +341,6 @@
      "Miller",
      59.84645669291338
     ],
-    [
-     "Hamwi",
-     56.413385826771645
-    ],
-    [
-     "Broca",
-     65.0
-    ],
-    [
-     "Broca (modified)",
-     55.25
-    ],
-    [
-     "Lorentz",
-     57.5
-    ],
-    [
-     "Creff (age)",
-     62.550000000000004
-    ],
     [
      "Peterson (BMI 22)",
      59.95
@@ -424,9 +384,9 @@
     ]
    ],
    "ideal_summary": [
-    58.98359580052493,
+    58.53474409448818,
-    55.25,
+    56.90944881889762,
-    65.0
+    59.95
    ],
    "healthy_range": [
     50.366249999999994,
@@ -695,26 +655,6 @@
      "Miller",
      null
     ],
-    [
-     "Hamwi",
-     null
-    ],
-    [
-     "Broca",
-     50.0
-    ],
-    [
-     "Broca (modified)",
-     42.5
-    ],
-    [
-     "Lorentz",
-     50.0
-    ],
-    [
-     "Creff (age)",
-     47.25
-    ],
     [
      "Peterson (BMI 22)",
      48.400000000000006
@@ -758,9 +698,9 @@
     ]
    ],
    "ideal_summary": [
-    47.63,
+    48.400000000000006,
-    42.5,
+    48.400000000000006,
-    50.0
+    48.400000000000006
    ],
    "healthy_range": [
     41.625,
@@ -1029,26 +969,6 @@
      "Miller",
      68.74566929133857
     ],
-    [
-     "Hamwi",
-     72.02362204724409
-    ],
-    [
-     "Broca",
-     75.0
-    ],
-    [
-     "Broca (modified)",
-     67.5
-    ],
-    [
-     "Lorentz",
-     68.75
-    ],
-    [
-     "Creff (age)",
-     69.03
-    ],
     [
      "Peterson (BMI 22)",
      67.65
@@ -1092,9 +1012,9 @@
     ]
    ],
    "ideal_summary": [
-    69.78548556430445,
+    68.94143700787401,
-    67.5,
+    67.65,
-    75.0
+    70.46456692913384
    ],
    "healthy_range": [
     56.65625,
@@ -1363,26 +1283,6 @@
      "Miller",
      77.62755905511811
     ],
-    [
-     "Hamwi",
-     89.03149606299212
-    ],
-    [
-     "Broca",
-     91.0
-    ],
-    [
-     "Broca (modified)",
-     81.9
-    ],
-    [
-     "Lorentz",
-     80.75
-    ],
-    [
-     "Creff (age)",
-     85.59
-    ],
     [
      "Peterson (BMI 22)",
      79.97
@@ -1426,9 +1326,9 @@
     ]
    ],
    "ideal_summary": [
-    83.52175853018372,
+    80.85608267716535,
     77.62755905511811,
-    91.0
+    84.9527559055118
    ],
    "healthy_range": [
     67.48985,