Every guide to filing a disability claim tells you the same thing: keep a symptom log. Almost none of them tell you what a useful entry looks like. So people write "bad headache day" for three months, hand over a notebook, and find that it does not say much.
The gap between a record that helps and one that does not is small, and it is mostly about being specific in five particular places.
The five parts of an entry
1. The date it happened
Not the date you got round to writing it down. If you are catching up on Sunday for a bad Wednesday, the entry is dated Wednesday.
This sounds obvious and it is the most common thing to get wrong, because catching up is normal and nobody thinks of the date as data. But the whole value of a log is that it shows a pattern over time. An entry dated to the day you wrote it, rather than the day it happened, quietly moves events around and makes the pattern less clear than your life actually was.
2. What happened, in plain words
Describe it the way you would to a friend, not the way you imagine a form wants it.
"Woke up at 3am with my back locked up, could not get comfortable again, gave up on sleep around 5" is a better sentence than "lumbar pain, severe." The second one sounds more official and carries less information.
You are not writing a diagnosis. You do not need the right medical term, and guessing at one can make the record worse rather than better. Describe what you felt and what happened. Somebody qualified can put a name on it later.
3. How bad it was
Pick one scale and use the same one every time. A zero-to-ten pain scale is fine. So is mild, moderate and severe. So is your own three-word scale, as long as it never changes.
The consistency matters more than the scale does. A record where the same words mean the same thing in January and in July shows something. A record where "bad" meant one thing in the spring and something else by autumn shows very little, because there is no way to tell a worsening condition from a shifting vocabulary.
It helps to write down, once, at the top of your log, what your scale means. Something like: 6 means I can still work but I am thinking about it constantly. Then use it.
4. How long it lasted
Start and end if you know them. A rough duration if you do not. "About four hours," "most of the afternoon," "still going when I went to bed."
Frequency and duration are different facts and both get asked about. Fourteen headaches a month that pass in twenty minutes is a different life from four that take out a whole day, and a log that records only the count cannot tell those apart.
5. What it stopped you doing
This is the one people leave out, and it is the one that carries the most weight.
A symptom on its own is a sensation. A symptom that stopped you doing something is an effect on your life, and effects on your life are what the whole process is trying to understand. Nobody can see your pain. They can understand "I left work at 1pm," "my wife drove because I could not," "I skipped my daughter's game," "I lay in a dark room until it passed."
Write the ordinary consequence, even when it feels too small to mention. Especially then. "Could not finish mowing the lawn" is a real fact about a real day. Over six months, thirty entries like that say something a hundred entries of "pain 7/10" cannot.
The same day, written two ways
Not useful:
March 4 — Migraine. Bad one.
Useful:
March 4 — Migraine started around 10am at work, light and noise both unbearable by 10:30. Severity 8. Took my medication, lay down in the break room with the lights off for about an hour, then drove home at noon and slept until 4. Missed the rest of the shift. Still felt wrung out that evening and went to bed early.
The second one took ninety seconds to write. It contains a date, a description, a severity, a duration, and three separate functional consequences: left work early, lost the afternoon, went to bed early. Nothing in it is exaggerated, and nothing in it is a medical claim.
Three things to leave out
Do not diagnose yourself. Describing a symptom is your job and it is genuinely useful. Naming the condition is not, and a wrong name in your own record is worse than no name.
Do not write what you think somebody wants to read. A log that reports the worst possible day every single day is less credible than an honest one, and it is obvious from the outside. The point of a record is that it is a record.
Do not editorialise about the process. Frustration with paperwork is entirely reasonable and it belongs somewhere other than the symptom log. Keep the log about the symptoms.
Log the good days too
This feels backwards and it is important.
A log with only bad days in it cannot show frequency, because there is nothing to compare against. Fifteen entries in a month means one thing if those are the only fifteen days you wrote anything, and something completely different if you wrote every day and fifteen of them were bad.
A one-line entry on a quiet day is enough. "Nothing much, ordinary day, some stiffness in the morning." It costs ten seconds and it turns your log from a list of complaints into a record of a life, which is what it is supposed to be.
Write it the same day
Memory for this kind of thing is worse than anybody expects. Severity flattens out within a couple of days, durations get rounded, and the small functional consequences — the ones doing the most work in your record — are exactly the details that vanish first.
An entry written the same evening, even a short one, is worth several written from memory at the end of the week. If you are choosing between a thorough entry three days late and a rough one tonight, write the rough one tonight.
The short version
Every entry: the date it happened, what happened, how bad, how long, and what it stopped you doing. Same scale every time. Good days as well as bad ones. Written the same day.
That is the whole method. It is not complicated, which is fortunate, because the only symptom log that helps anybody is one that actually gets kept.