Psychology
ADHD in children: signs, diagnosis and treatment
ADHD is more than an active child. What the signs are, what else can look like it, how it is assessed, and which treatments help at each age.
27 Sept 20269 min read
Symptom
A symptom is something a patient notices and reports — pain, nausea, tiredness. It differs from a sign, which is something a doctor can observe or measure.
The distinction between symptom and sign is not pedantry — it separates two different kinds of evidence. A symptom is subjective and only the patient has access to it: nobody can measure someone else's pain. A sign is objective and observable by another person: a rash, a murmur, a temperature, a swollen ankle. A single finding can be both, as breathlessness is when a patient feels it and a doctor counts the breathing rate.
Because symptoms are the only evidence available before any examination, how they are described does a large share of the diagnostic work. When something started, how it began, what makes it better or worse, whether it is constant or comes in episodes, and what else changed at the same time — these narrow a more efficiently than most tests do.
Where this comes up
Mental Health
Anxiety: When Worry Becomes an Illness
Anxiety is a real illness with real physical symptoms, and it responds to treatment. What helps, what makes it worse, and why alprazolam is the wrong first answer.
29 Aug 202612 min read
Tests & Diagnostics
Complete Blood Count (CBC): How to Read Your Report
Line by line through a CBC report — haemoglobin, MCV, the white cell differential and platelets — with what a flagged value usually means and what it does not.
29 Aug 202612 min read
Mental Health
Depression: Telling It Apart From Ordinary Sadness
Depression is not weakness or a lack of faith. How to tell it from ordinary sadness, what treatment involves, and what to do if someone is thinking of ending their life.
29 Aug 202613 min read
Related terms
- Differential diagnosisDifferentials, The list of possibilitiesA differential diagnosis is the list of conditions that could explain a person's symptoms, ranked by likelihood and by danger. It is how a doctor thinks before a diagnosis is reached, and the reason questions and tests follow the order they do.
- PrognosisOutlookA prognosis is the expected course of a condition — how it is likely to develop and what the chances of recovery are. It is a statement about probability across many people, not a prediction about one.
- ScreeningScreening testScreening is testing people who feel well, to find a condition earlier than symptoms would. It is only worth doing when finding the condition early genuinely changes what happens next.
- Side effectAdverse effect, Adverse drug reactionA side effect is any effect of a medicine other than the one it was given for. Some are trivial and settle, some are the reason a medicine has to be stopped.