Social Rhythm Metric: the five daily anchors researchers log, and how to log them yourself

The Social Rhythm Metric (SRM) is a diary instrument, introduced by Monk, Flaherty, Frank, Hoskinson and Kupfer in 1990 in the Journal of Nervous and Mental Disease, that scores how regular a person’s daily routine is. The original logs 17 daily events; the short form, SRM-5, published in 2002 by Monk, Frank, Potts and Kupfer, logs five.

It is a research tool from the Pittsburgh group that built interpersonal and social rhythm therapy, and it was designed to measure the routine, not to diagnose anyone. The idea behind it, that other people act as clocks for the body, is covered in the social zeitgeber explainer. This post is about the instrument itself. Some people who want a steady first-contact anchor ask a friend to be part of it, and DontSnooze is one app built around that idea.

What are the five SRM-5 items?

The 2002 paper picked five of the 17 original items and calculated scores as if those were the only ones collected. They are below, with what each is for.

#	Anchor	What you write down
1	Get out of bed	The time you get up
2	First contact with another person	The first time you see or speak to someone, in person or by call
3	Start work, housework or volunteer activities	The time the day’s main task begins
4	Have dinner	The time you sit down to eat it
5	Go to bed	The time you get into bed

Five items are far less work than 17, and the results below show they tracked the long version well.

How is regularity scored?

The scoring rule I could verify comes from Carnegie Mellon’s description of the 17-item version. An event counts as regular if it happens at least three times a week. A day counts as on schedule for that event if the event falls within 45 minutes of its habitual time, which is the person’s average, with outliers beyond 1.5 standard deviations set aside. The score is built from how often regular events land inside that 45-minute window.

I am unsure how the published SRM-5 score is scaled. The 2002 abstract reports a mean of 4.11 and a standard deviation of 1.13, but it does not state the range, and the Carnegie Mellon page, which covers the longer version, is not consistent about its own item count. Cutoff conventions also seem to differ between versions of the instrument. So treat the method below as a simplified home count, not the official score.

What did the SRM-5 study find?

Scores from the five-item version correlated about 0.8 with the 17-item version, both across people and within one person over time. As a detector of irregularity, defined by the long version’s scores, it had a kappa of 0.69, a sensitivity of 74% and a specificity of 95%. It ran higher than the long form by about 0.9 units, roughly one standard deviation.

How do you keep a 14-day log on paper?

Fourteen days is the length the healthy-adult studies used. Here is a layout. Times are in 24-hour clock; after midnight is fine.

Day   Out of bed   First contact   Start work   Dinner   In bed
 1      6:40          7:15            8:30       18:45    23:10
 2      6:35          7:30            8:25       19:20    23:40
 3      8:05          9:40           10:00       18:50     0:25

Then follow the five steps above. These rows are invented. Day 3 is the kind of drift the count is made to catch: with a usual getting-up time of about 6:40, 8:05 is 85 minutes off, 40 minutes outside the window.

After the log, look at the miss pattern. If one column accounts for most misses, that is the anchor to settle first. If every column drifts together, look for one event that moved them all, such as a night of poor sleep or a shift change. The same grid is useful when a job that used to set the start-of-work column goes away, which is the situation described in this piece on retirement and sleep drift.

Why do clinicians care about regularity?

In a randomized trial of 175 acutely ill people with bipolar I disorder (Frank et al., 2005, Archives of General Psychiatry), those assigned to interpersonal and social rhythm therapy in the acute phase survived longer without a new mood episode (P = .01) than those assigned to intensive clinical management. They also had higher rhythm regularity at the end of acute treatment, and people who increased their regularity were less likely to have a recurrence in the two-year maintenance phase (P = .05). The trial does not show that a tidy schedule prevents episodes in anyone else, and it is not a case for using a paper diary in place of treatment. Bipolar disorder belongs with a clinician.

What the SRM cannot tell you

It records timing, not quality. A perfectly regular day can still be a bad day. It relies on memory and honesty, and a five-item version ignores meals, exercise and naps that the long form includes. The healthy-adult norms say little about shift workers, new parents or anyone whose life is not built around a daytime schedule. Your own number across a few weeks says more than any comparison.