How to measure feeling better, which is real but fuzzy

Key takeaways

• In a British study of 212 adults who wore step counters for four weeks, a single day was a poor guide to a person’s month, while one full week predicted it well.
• On the PHQ-9, a nine-question depression questionnaire scored from 0 to 27, a study of older adults in depression care found that a 5-point change was the smallest that mattered for one person.
• On the WHO-5 well-being index, scored from 0 to 100, a change of 10 points counts as meaningful, and a score of 50 or below is a signal to check for depression.
• The American Academy of Sleep Medicine suggests keeping a sleep diary daily for about two weeks, and treats insomnia on three nights a week for three months as chronic.
• Any thought of harming yourself is a reason to reach out now: call or text 988, or call 911 in an emergency.

British researchers asked 212 adults in England’s East Midlands to wear a step counter every day for 28 days¹⁴. Then they asked a practical question. How many days of data do you need to know someone’s typical month?

One day turned out to be a poor guide¹⁴. Any three days still fell short. A full week did the job: the first week’s average predicted the month’s average closely¹⁴.

Sundays stood out. People took about 7,700 steps on Sundays, compared with roughly 9,200 to 9,800 on other days, so the researchers advised always including a Sunday¹⁴.

Your sense of “I feel better” has the same problem. One great morning or one awful night can sway your judgment. So can the week you started something new, when hope runs high.

Feeling better is real. But if you want to know whether a new bedtime routine, a walking habit or an herbal tea is helping, you need something steadier than a single day’s impression. Researchers and clinics use simple, tested measures for this. Most take a few minutes.

Why “I feel better” deserves a number

Many natural-health traditions ask you to listen to your body. A measure is a way of listening carefully, at the same time each day, with the same question. It doesn’t replace your judgment. It gives your judgment better evidence.

Good measurement follows three rules. Measure before you change anything, so you know your normal. Change one thing at a time. And compare averages, not single days, because daily numbers bounce around¹⁴.

Our article on self-trials explains how to set up a fair test of a remedy. This article covers the measuring tools for four things people most want to improve: sleep, activity, energy and mood.

Sleep: a two-week diary beats your memory

A sleep diary is the classic tool. Each morning, the American Academy of Sleep Medicine (AASM) suggests, jot down your bedtime, any wakings in the night and the time you got up⁹. Add when you napped, exercised, took medicines, and had caffeine or alcohol⁹.

AASM says two weeks is typical and that daily entries work best⁹. The finished diary shows your clinician your real schedule and can point to habits behind a sleep problem, such as a late coffee⁹.

From a diary, you can work out a few useful numbers:

• Time asleep: hours in bed minus the time it took to fall asleep and the time spent awake during the night.
• Time to fall asleep: your best estimate, in minutes.
• Night wakings: how many, and roughly how long.
• Sleep efficiency: time asleep divided by time in bed. It rises when less of your night is spent lying awake.

Compare your time asleep with CDC’s recommendations: 7 or more hours for adults ages 18 to 60, 7 to 9 hours for ages 61 to 64, and 7 to 8 hours for those 65 and older¹⁰. CDC lists trouble falling asleep, waking repeatedly and feeling tired after enough sleep as signs of poor sleep quality¹⁰.

A wearable can estimate these numbers for you. Our article on sleep trackers explains why their hours are fairly good and their sleep stages are rough guesses.

Activity: average a full week, and rate your effort

Steps are the easiest activity measure to collect, because most phones already count them. The trick is to average a full week, including a weekend day, rather than react to any one day¹⁴.

How many steps matter? A 2022 analysis in The Lancet Public Health pooled 15 studies of 47,471 adults followed for a median of about seven years¹³. People in the top quarter, with a median of about 10,900 steps a day, had roughly half the risk of dying during follow-up of those in the bottom quarter, at about 3,550 steps¹³.

The benefit leveled off. For adults 60 and older, risk stopped falling at about 6,000 to 8,000 steps a day. For younger adults, the plateau came at about 8,000 to 10,000¹³. These were observational studies, so they show a link, not proof that steps alone caused the difference.

Steps don’t capture effort, so add a second measure. CDC describes a simple 0-to-10 scale where 0 is sitting still and 10 is your hardest possible effort¹². Moderate activity is about a 5 or 6, and vigorous activity starts at about 7 or 8¹².

The talk test is a quick check. During moderate activity you can talk but not sing¹². During vigorous activity you need to stop for a breath after just a few words¹².

A useful weekly activity record, then, is two numbers: your average daily steps and the number of minutes you spent at a 5 or higher.

Energy: the hardest thing to pin down

“Low energy” can mean sleepy, weak, unmotivated or foggy, and it has many causes. MedlinePlus, the National Library of Medicine’s consumer site, lists anemia, depression, sleep apnea, thyroid problems, diabetes, heart failure, kidney disease and many medicines among them¹⁵.

For a research-grade measure, look to PROMIS, a set of questionnaires developed with NIH funding starting in 2004¹. Its measures cover fatigue, physical function, pain, depression, anxiety and sleep disturbance, among other areas²³. Scores use a T-score scale, where 50 is the average for the general population and every 10 points is one standard deviation, a common measure of spread¹.

What counts as a real change on PROMIS? A 2021 systematic review in Quality of Life Research set aside studies with weaker methods and kept 31 estimates. They ranged from 0.1 to 12.7 points³. For treatments other than surgery, the authors called 2 to 6 points a reasonable working range³.

They also cautioned that these thresholds describe groups. Applied to one person, they can misclassify some people³.

The PROMIS Health Organization holds the copyright. For the PROMIS sleep measure, a summary by the Critical Path Institute, a nonprofit research group, says paper use in English or Spanish is free and clinicians may copy it for their own patients, while electronic and other uses need written permission and can carry fees². Terms differ by language and format². Ask your clinician whether they use PROMIS, or check with HealthMeasures, the Northwestern University center that distributes the forms and explains how to license them¹.

For daily use, many people simply rate their energy from 0 to 10 at the same time each day. That’s a practical habit, not a validated scale, so rely on weekly averages and keep the question the same.

Mood: screening questionnaires, not diagnoses

Two short questionnaires are widely used to check mood over the past two weeks.

The WHO-5 well-being index asks five positively worded questions about feeling cheerful, calm and energetic, waking rested, and finding daily life interesting⁸. Each is rated from 0 to 5, and the total is multiplied by 4 for a score from 0 to 100, where higher is better⁸.

A 2015 systematic review of 213 published studies found it worked well both for tracking change and for screening⁸. The review recommends a score of 50 or below as the signal to check for depression⁸. Pooling 18 studies, it caught 86% of people with depression and correctly cleared 81% of those without it⁸. A change of 10 points is considered meaningful⁸.

The PHQ-9 asks about nine symptoms of depression over the past two weeks, each scored from 0 (not at all) to 3 (nearly every day), for a total from 0 to 27⁴. In the 2001 study that introduced it, about 6,000 patients in primary care and obstetrics-gynecology clinics completed it⁴.

Scores of 5, 10, 15 and 20 marked mild, moderate, moderately severe and severe depression⁴. Among 580 patients who also had an interview with a mental health professional, a score of 10 or higher picked up 88% of those with major depression and correctly cleared 88% of those without it⁴. Researchers Kurt Kroenke, Robert Spitzer and Janet Williams developed it with an educational grant from Pfizer⁴.

For tracking, a 2004 study of 434 older adults in depression treatment found that a 5-point change was the smallest that mattered for an individual⁵.

These tools flag likely problems. They don’t diagnose. In the PHQ-9’s original design, a clinician confirms the answers and rules out physical causes before making a diagnosis⁴. The U.S. Preventive Services Task Force recommends depression screening for all adults, and says every positive screen should lead to a fuller assessment⁶.

The last PHQ-9 question asks about thoughts of death or self-harm⁴. Any “yes” to that question deserves a conversation right away, whatever your total score.

What counts as a real change

Two weeks of data on each side of a change is a sensible minimum, because most of these measures use a two-week window⁴⁸⁹. Then compare averages.

What you’re tracking	How often	A change worth noticing
Sleep diary	Daily, for two weeks before and after a change9	A steady shift in your two-week average, beyond your normal swing
Steps	Daily; compare weekly averages that include a Sunday14	Use your own baseline; benefits level off around 6,000 to 10,000 steps, depending on age13
Effort (0 to 10)	Each workout	More minutes at 5 or higher in a typical week12
PROMIS short forms	Every week or two; the sleep form asks about the past 7 days2	About 2 to 6 points, as a rough guide3
WHO-5	Every two weeks8	10 points or more8
PHQ-9	Every two weeks4	5 points or more5

For your own 0-to-10 ratings, here’s a practical rule of thumb, not a tested formula. During your baseline weeks, note your highest and lowest weekly averages. A change that lands outside that range is more likely to be real than a change inside it.

Our article on meaningful benefit explains why “statistically significant” and “worth it” aren’t the same thing.

A monthly check-in form

Print this, or copy it into a notebook. Fill in Part 1 each week and the rest once a month.

Part 1: Weekly averages

Week	Hours asleep	Minutes to fall asleep	Steps per day	Minutes at effort 5+	Energy (0-10)	Mood (0-10)
Baseline 1	______	______	______	______	______	______
Baseline 2	______	______	______	______	______	______
Week 1	______	______	______	______	______	______
Week 2	______	______	______	______	______	______
Week 3	______	______	______	______	______	______
Week 4	______	______	______	______	______	______

Part 2: Questionnaire scores

• WHO-5 or PROMIS score, if you use one. Baseline: __. This month: ____.
• PHQ-9 score, if your clinician uses it. Baseline: __. This month: ____.

Part 3: The monthly review

• The one change I made this month: ________
• Other things that changed anyway (illness, travel, stress, new medicines): ________
• Did any average move outside my baseline range? Which ones? ________
• Red-flag check (see the next section). Any yes? Yes / No
• My decision: keep it / adjust it / stop it / talk with my clinician.

When a score means talk to someone

Numbers can reassure you, but some should prompt a call.

Right away

• Any thoughts of suicide or self-harm. Call or text the 988 Suicide and Crisis Lifeline, or chat at 988lifeline.org. In a life-threatening emergency, call 911⁷.
• Fatigue with confusion, dizziness, blurred vision, little or no urine, or recent swelling and weight gain. MedlinePlus says to contact your provider right away¹⁵.

Soon, with an appointment

• A low mood or loss of interest that lasts most of each day, almost daily, for two weeks or more⁷.
• A WHO-5 score of 50 or below, or a PHQ-9 score of 10 or higher⁴⁸.
• Trouble sleeping at least three nights a week for three months. AASM calls this chronic insomnia and recommends cognitive behavioral therapy for insomnia (CBT-I), a structured program that retrains sleep habits¹¹.
• Feeling tired even after enough sleep, or signs of a sleep disorder such as sleep apnea¹⁰.
• Unexplained fatigue, especially with fever, unplanned weight loss or regular sweats¹⁵.
• Fatigue that doesn’t improve with good sleep, food and lower stress¹⁵.

Depression is treatable, usually with talk therapy, medicine or both, according to the National Institute of Mental Health⁷. Bringing two months of scores to your visit gives your clinician far more to work with than “I’ve been tired.”

What the evidence shows

Claim	Evidence rating	What it rests on
The PHQ-9 accurately flags likely major depression and grades its severity	Strong evidence	About 6,000 clinic patients; 88% sensitivity and specificity at a score of 10 in 580 who had an expert interview4
A 5-point PHQ-9 change is meaningful for one person	Promising but early	One study of 434 older adults in treatment5
The WHO-5 works as a screen and as a measure of change	Strong evidence	Systematic review of 213 studies8
A 2 to 6 point PROMIS change is meaningful	Promising but early	Estimates ranged from 0.1 to 12.7 points; group thresholds can misclassify individuals3
One week of step counts represents your month	Promising but early	One study of 212 adults14
More daily steps are linked to lower death risk, up to a plateau	Strong evidence	15 studies, 47,471 adults; observational, so it shows a link13
A daily 0-to-10 energy or mood rating is a validated measure	Not enough evidence	A practical habit; use weekly averages and the same question each day

Questions readers ask

The bottom line

Feeling better counts. Measuring helps you trust it. A two-week sleep diary, a weekly step average, a 0-to-10 effort rating and a short mood questionnaire every two weeks can show whether a change is working, and they take minutes.

Use averages, not single days, and compare them with your own baseline. Know the few scores that mean you should call someone, and treat any thought of self-harm as a reason to reach out right away.

Related reading

• Feeling better after trying something isn’t a test, but you can run one
• A 22% risk cut can mean helping 2 or 3 people in 1,000
• Sleep trackers count your hours well, but their sleep stages are rough guesses
• Your wearable’s best number is your own normal, not the average
• Walking clubs work, and you need fewer steps than you were told

Sources

1. HealthMeasures, Northwestern University. “PROMIS (Patient-Reported Outcomes Measurement Information System).” HealthMeasures, accessed October 2026. healthmeasures.net
2. Critical Path Institute, Rare Disease Clinical Outcome Assessment Resource. “Patient-Reported Outcomes Measurement Information System Bank v1.0 Sleep Disturbance” (COA at-a-glance). C-Path, accessed October 2026. rdcoas.c-path.org
3. Terwee CB, Peipert JD, Chapman R, et al. “Minimal Important Change (MIC): A Conceptual Clarification and Systematic Review of MIC Estimates of PROMIS Measures.” Quality of Life Research, 2021;30(10):2729-2754. link.springer.com
4. Kroenke K, Spitzer RL, Williams JBW. “The PHQ-9: Validity of a Brief Depression Severity Measure.” Journal of General Internal Medicine, 2001;16(9):606-613 (copy hosted by the Indian Health Service). ihs.gov
5. Löwe B, Unützer J, Callahan CM, Perkins AJ, Kroenke K. “Monitoring Depression Treatment Outcomes With the Patient Health Questionnaire-9.” 2004 (University Medical Center Hamburg-Eppendorf research record; PubMed ID 15550799). pubmed.ncbi.nlm.nih.gov
6. U.S. Preventive Services Task Force. “Depression and Suicide Risk in Adults: Screening.” USPSTF, June 20, 2023. uspreventiveservicestaskforce.org
7. National Institute of Mental Health. “Depression.” NIH Publication No. 24-MH-8079, revised 2024. nimh.nih.gov
8. Topp CW, Østergaard SD, Søndergaard S, Bech P. “The WHO-5 Well-Being Index: A Systematic Review of the Literature.” Psychotherapy and Psychosomatics, 2015;84(3):167-176. pubmed.ncbi.nlm.nih.gov
9. American Academy of Sleep Medicine. “Sleep Diary.” Sleep Education, updated March 2021. sleepeducation.org
10. Centers for Disease Control and Prevention. “About Sleep.” CDC, May 15, 2024. cdc.gov
11. American Academy of Sleep Medicine. “Insomnia.” Sleep Education, reviewed September 2020. sleepeducation.org
12. Centers for Disease Control and Prevention. “Measuring Physical Activity Intensity.” CDC, December 4, 2025. cdc.gov
13. Paluch AE, et al., Steps for Health Collaborative. “Daily Steps and All-Cause Mortality: A Meta-analysis of 15 International Cohorts.” The Lancet Public Health, 2022;7(3):e219-e228. scholars.uthscsa.edu
14. Clemes SA, Griffiths PL. “How Many Days of Pedometer Monitoring Predict Monthly Ambulatory Activity in Adults?” Medicine & Science in Sports & Exercise (accepted manuscript marked “in press,” Loughborough University Repository). pubmed.ncbi.nlm.nih.gov
15. MedlinePlus, National Library of Medicine. “Fatigue.” Medical Encyclopedia, reviewed May 19, 2025. medlineplus.gov