Close four findings from the health-score audit:
- Hypotension cliff: the below-floor branch reused the over-target table,
so 1 mmHg under the clinical floor dropped from 100 to ~81 — a 19-point
discontinuity. A dedicated under-floor curve now starts at 100 AT the
floor and descends smoothly (floor-10->70, -20->45, -30->20), so the
score is continuous on both sides of every boundary on both axes.
- Rollup vs live divergence: the graded BP score weighed a high-variance
day 1:1 on the rollup path (one per-day-mean pair) but N:1 on the live
path (N per-event pairs), drifting the pillar by up to ~20 points
depending on DAY-bucket warmth. gradeBpScoreFromSeries now takes an
optional per-pair count; the rollup path passes perDayPairCount so both
paths produce the same score for the same data.
- Resting proxy degenerate days: a day with fewer than three PULSE
samples no longer contributes a resting estimate, so a lone workout
reading can't masquerade as resting HR.
- Pulse-status proxy day boundary: thread the user's timezone into the
resting-proxy day-key so it buckets identically to the targets route.
Fairness anchors unchanged (134/87 -> 57, 165/105 -> 22).
The BP pillar value equalled the binary all-time in-target rate: the
share of paired readings where both systolic and diastolic sat at or
below the age-band ceiling. A borderline stage-1 profile (diastolic a
few mmHg over the ceiling on most readings) collapsed the pillar to the
teens even though the reading is "a bit high", not catastrophic — and
improvement never surfaced because the rate is all-time and binary.
Replace the binary rate AS THE SCORE with a smooth clinical-proximity
grade. A recency-weighted representative reading (45-day half-life) is
mapped per axis onto a 0-100 curve anchored on the same age-band ceiling
the rest of the app uses — optimal ≈ 100, at the ceiling ≈ 85, then
piecewise-linear down through the over-target bands; hypotension is
penalised symmetrically below the clinical floors. The pillar takes the
worse of the two axes, so an elevated diastolic counts without
binary-zeroing the result. A 134/87 profile against a 129/79 ceiling now
reads in the mid-50s.
The in-target rate stays available as a secondary "X% of readings in
range" stat. The healthScore.components.bp shape is unchanged — only the
value moves.
Marc-André Bombeck