A bladder diary is a written record of what you drink, what you pass and when, kept for a few days so that your clinician can see the pattern instead of relying on memory, which tends to get the numbers wrong.1 Keeping one comes down to four habits: write the time straight away, note every drink with its amount, measure urine when you can and tick the trip when you can’t, and mark what happened at night.

Your urologist, GP, nurse or pelvic-floor physiotherapist may call it a voiding diary, a frequency–volume chart or a micturition diary; the International Continence Society defines each of these terms.2,3 In hospital the same record is an input and output chart. The columns are near enough the same; the name depends on who hands you the sheet.

What a bladder diary is for, and why you were asked

The diary answers questions an appointment can’t. How often do you go over a full day and night? How much comes out each time? How does that relate to what you drank, and when? How many times do you get up at night?

The International Continence Society defines a frequency–volume chart as a record of the time and volume of every void for at least 24 hours, and a bladder diary as the same record plus fluid intake, leaks and pad use.2,3 Clinics ask for one before a first appointment and use it again to see whether treatment is working.4 What the numbers mean is your clinician’s call. Your job is a record that is complete and honest.

What to record in a bladder diary

A bladder diary has five columns: the time, what you drank and how much, how much you passed (or a tick for not measured), whether it was at night, and a note. Five columns cover almost every clinic’s form.

  • Time. Every drink and every trip, written when it happens. The time matters as much as the amount: the same volume at three in the afternoon and at three in the morning tells a clinician different things.
  • What you drank, and how much. The type and the amount: 250 ml of tea, a 330 ml can, a 500 ml bottle. Measure your usual mug, glass and bottle once with a measuring jug and reuse the numbers.
  • How much you passed. In millilitres or fluid ounces, from a measuring jug or a collection “hat” that sits under the toilet seat. If you passed urine but couldn’t measure it, put a tick and keep the time. The NHS chart says exactly that.5
  • Night. Write down when you went to bed and when you got up, and mark every trip in between.5,6 With the bed and wake times on the sheet, your clinician can separate day from night.
  • Notes. A strong urge, a leak and roughly how much, a pad change, pain, anything unusual. Some forms have separate columns for urgency and leaks; if yours does, use them.

Before you start

  1. Get something to measure with. Any kitchen jug marked in millilitres will do; the Urology Care Foundation suggests a kitchen measuring cup or a cup you know holds a set amount.7 Clinics often hand out a collection hat. Keep it by the toilet and rinse it after each use.
  2. Measure your everyday cups once. Your mug, your glass, your water bottle. From then on you write the number, not a guess.
  3. Pick the days. Most clinics ask for three; some ask for seven, and the research on how long a diary should run points the same way.9 NICE’s quality standard for women with urinary incontinence asks for at least three days that cover both working and leisure days,4 and the Urology Care Foundation asks for three typical days that need not be in a row.7 If you were told a number, use that one.
  4. Keep the sheet where you’ll use it. By the toilet, in a pocket, or on your phone. A diary you don’t have with you can’t be filled in.
  5. Carry on as usual. The diary is meant to show normal days.8 Don’t drink less to make it look tidier.

A filled-in day, line by line

Here are three lines from the worked example on the first page of our printable template:

Three example rows from the printable template: 7:20, drank 250 ml of tea, passed 320 ml; 9:40, a tick for not measured, with the note “in a hurry, small leak”; 3:10, passed 180 ml, ticked as night

  • 7:20. A cup of tea, 250 ml, and the first trip of the morning, 320 ml, measured with the jug.
  • 9:40. A trip in a hurry: no time to measure, so a tick instead of a number, and a note about a small leak. The trip still counts.
  • 3:10. 180 ml in the middle of the night. It gets a tick in the Night column because it happened between going to bed and getting up.

Three lines, and a clinician already sees a measured void, an unmeasured one that still counts, and a night trip with its volume. A full day has more lines, but each one is just as simple.

Or keep the same diary in the Bladder Diary: Fluid Balance app: the same columns, two taps per entry, always in your pocket, and free.

Mistakes that spoil a diary

  • Filling it in from memory in the evening. Times drift and the small trips vanish; even the number of trips is misremembered.1 Write as you go.
  • Skipping a trip because you couldn’t measure. A ticked trip with a time still shows how often you go and how many times you got up at night. A missing trip shows nothing. An estimate is better than a gap.
  • Leaving out the bed and wake times. Without them, night trips can’t be counted.
  • Stopping halfway. Two complete days are worth more than four with holes. Completeness is the first thing a clinician checks.
  • Changing your habits for the diary. Skipping your evening tea for three days hides exactly the pattern the diary is meant to show.

Bringing it to the appointment

Bring every page, including the days with gaps, and say which days are complete.7,8 Our template has a line for that on the last page: days recorded, out of seven. Take a photo of each page as a backup before you hand it over.

If you kept the diary in an app, export the report and print it, email it to the clinic, or show it on your phone. Some clinicians prefer paper; a printed page is never wrong.

If you started or stopped a medicine during the diary days, write it in the notes. Don’t change anything for the diary’s sake.

Paper or app

A paper sheet works, and clinics are used to it. An app adds the time automatically, does the totals and produces a report at the end. If you prefer paper, the free template has the same columns as the app, in A4 and US Letter, as full pages or fold-in-half booklets. If you prefer the phone, Bladder Diary: Fluid Balance takes two taps per entry and never comments on your numbers.

Who is asked to keep one

Nocturia, overactive bladder, incontinence, follow-up after a urinary infection, an enlarged prostate before and after surgery, pelvic-floor physiotherapy, recovery after a catheter. The record is the same in every case. What the clinician looks for in it differs, and that part is theirs.