What "baseline" means in bipolar mood tracking

"Baseline" gets used a lot and defined rarely. In mood tracking, your baseline is what your data looks like when nothing is wrong — the steady state that gives bad weeks something to be measured against.

Without a baseline, every hard day looks like a crisis and every good day looks like a recovery. With one, you can tell the noise from the signal.

What it is and is not

Your baseline is not zero. It is not the day you felt "perfectly fine." It is the typical range your scales settle into across weeks when no episode is active.

For most people on a 0–3 mood scale, baseline looks like:

• Mostly 0s and 1s on depression
• Mostly 0s on elevation, with the occasional 1
• A range of 0s and 1s on anxiety and irritability that reflects life
• Sleep within a familiar window, give or take an hour

The exact range is yours, not anyone else's. The point is not the numbers; it is the consistency.

How to find yours

You need data — not a perfect month, just a representative one. Ambulatory data over weeks gives you a baseline that retrospective interviews cannot2013.

The recipe:

1. Log every day for at least three to four weeks (longer is better) during a stretch when nothing major is happening
2. Skim the chart — what range do most days fall into?
3. Write it down. "My baseline depression is mostly 0–1, elevation mostly 0, sleep 6.5 to 8 hours."

That sentence is your reference. Future you can compare against it.

Why baselines drift

Baselines are not fixed forever. They shift with:

• Medication changes (intentional shifts in either direction)
• Major life changes (move, relationship, job)
• Aging
• Untreated patterns (a slowly worsening baseline can be its own warning)

A baseline review every six months is enough. The chart will tell you whether your numbers have moved.

Why it matters for episodes

The point of a baseline is to make "not baseline" visible. Smartphone-based mood monitoring works in part because it surfaces deviations from a person's typical pattern2015.

The day your depression score sits at 2 for the third day in a row is a different day if your baseline is mostly 0s and 1s than if your baseline already includes regular 2s. Both are real. Only one needs the same response.

What to do with the baseline

Three uses:

1. Personal alarm threshold. "Two weeks above baseline on depression is when I call my clinician." You set it.
2. Visit prep framing. "Compared to my usual range, this month was higher on irritability and lower on sleep."
3. Treatment decisions. A medication change that moves baseline toward a healthier range is doing its job; one that does not is data for the next conversation.

What a baseline is not

This is not a clinical instrument. It is a personal reference, derived from your own data, in your own life. The value comes from being honest about what your typical week looks like, not from comparing yours to anyone else's.