🩺 Quarterly Audit · 11 min read · Subtopic 4 of 5

The Year-over-Year View

Quarter-to-quarter shows movement; year-over-year shows trajectory. The two are different claims, and the sheet's year column exists so you can tell them apart. This page is the annual comparison: why this quarter against the same quarter last year is the real story, how the slow-moving labs read on a yearly scale, and the rollover mechanic that turns four quarters into a year's worth of signal.

🔎 Evidence Snapshot ★★★☆☆ Moderate — annual biomarkers carry strong cohort evidence; the year-over-year reading rule is practical design

What the evidence supports

  • Slow-moving biomarkers like HbA1c reflect roughly two to three months of glycemic state, so annual spacing captures the part that matters (Selvin 2010).
  • Long-term trends in weight, strength, and metabolic measures carry stronger associations with outcomes than single snapshots (Zheng 2017; Celis-Morales 2018).
  • Seasonality is real and well documented, which is why same-season comparisons are the honest ones (Hodgkinson 2011).

What remains uncertain

  • How many years of back-history genuinely sharpen a decision is untested; three to five years of annual labs is a practical convention.
  • Whether the act of annual comparison itself changes outcomes is unknown — its value is the earlier, better-informed conversation, not a measured effect.

Evidence last reviewed: August 20, 2026. Conclusions may change as new research is published.

one sheet per quarter

Two Comparisons, Two Questions

Nearly every mistake in reading a tracking sheet comes from asking the wrong comparison the wrong question. This-quarter-versus-last-quarter is the short check — did anything move in ninety days? This-quarter-versus-last-year is the long view — is my trajectory the same, better, or worse than a year ago, once the season is subtracted out? The audit's whole design, set up in the Quarterly Self-Audit series lead, assumes you will ask both, in that order, and treat the answers as different kinds of evidence: movement is a prompt; trajectory is a story.

The Slow-Moving Labs Read on a Yearly Scale

The three annual labs — ApoB, HbA1c, and fasting glucose — move on a scale of months to years, and the quarterly sheet must not pretend otherwise. HbA1c integrates roughly two to three months of average glucose, so a single year's annual reading is the honest unit of change; ApoB changes even more slowly, responding to diet, weight, and sometimes medication over the course of a year or longer. Full detail on what each measures and what a change may mean lives in Blood Markers; this page only handles how the year view reads them.

How Long Each Record Stays Useful
A convention for how much history each record deserves — the point is that slow labs outlive the rolling quarter
Annual labs (ApoB, HbA1c, glucose) 3–5 years, in a file Quarterly home measures rolling year on the sheet Sleep and daily logs weeks to a month slow labs deserve years of history; the quarterly sheet deserves a rolling year — the archive matches the timescale

The Rollover Mechanic

Once a year, the sheet performs its one structural act: the rollover. Four completed quarters become the year that just happened; the new year starts fresh with today's values. The mechanic is simple and worth doing deliberately, because it is the moment the year's story gets written down while it is still legible.

RecordTimescale it servesWhere it livesRollover job
🗂️ One-page sheetThe rolling yearFridge or visible deskShift columns, write the year line, file
📊 Lab archive tabThree to five yearsSpreadsheet or envelopeAdd the year's ApoB, HbA1c, glucose rows
🗓️ The year lineOne sentence, one yearBottom of the old sheetThe story that makes old numbers legible

A Year of Comparisons, Worked

Put the pieces together on a real quarter. Home blood pressure reads 128/82 this Q1 against 132/84 a year ago — four mmHg systolic lower year-over-year, inside no single quarter's noise but clear over a year, and the context line reads "started morning walks." That is a trajectory with a mechanism and a magnitude; it is the exact claim the year column exists to make. Now the reverse: this Q1's 130/84 against last quarter's noisy 124/78 looks like a jump, but the year-ago value is 130/82 — flat as a lake. The short check lied and the long view told the truth. That is the entire argument of this page in two sentences.

🗓️ Same season, not same week

The year view only means anything when the sampling lines up. Compare Q1 to Q1, mornings to mornings, a seven-day average to a seven-day average. When the method drifts, the "change" the year column reports is partly a change in how you measured — annotate the method and count that drift separately from your trend.

3–5
years of annual lab history worth keeping for slow movers
1
year line — the one sentence that makes old sheets legible
2
questions per comparison — did it move, and is the trajectory real

What a Year Does Not Tell You

A year of comparisons is powerful evidence of direction and remarkably silent about cause. A rise in waist-to-height over a year is a real, watchable trend — but the sheet cannot tell you whether it is the new job, the nutrient, the sleep loss, or several of them together. Causation is a conversation for a clinician with your history, not a conclusion the sheet can draw. The year view's discipline is the same as the quarterly one: it reports movement honestly and leaves interpretation to the people licensed to make it. For the records that belong at that visit, the Doctor's-Visit Bonus page covers the handoff; the review habits that keep the annual pass from slipping are the Review Systems protocol's domain.

Questions, Answered Briefly

The Bottom Line

  1. Quarter movement, year trajectory — different claims. The short check finds candidates; the year column verdicts them.
  2. Slow labs deserve years. ApoB, HbA1c, and glucose read on an annual scale and repay a three-to-five-year archive.
  3. The rollover is the annual ritual. Shift columns, write one year line, file the old sheet, and set one theme for the year.
  4. The year view shows direction, not cause. Interpretation of a real trend belongs to a clinician, not the page.

Related Topics

Sources & further reading