Summary of various symptom outcome measures in clinical trials of patients with heartburn
| Definition | Comment | Example of studies where outcome measure was used | |
|---|---|---|---|
| Heartburn resolution | No symptoms in the last 7 days of therapy. | Patient assessment by diary cards | Castell13 |
| ⩽1 day with no more than mild heartburn episode in the past 7 days | Heartburn frequency and severity recorded by diary card | Lind4 | |
| Adequate control (or relief) of heartburn | Patient’s assessment in response to the question: “does the study medication give sufficient control of your heartburn?” | Lind4 | |
| Response | Symptoms improved by at least two grades (on 4 grade modified Likert scale) or from mild to none | Bate44 | |
| Symptoms improved by at least three grades (on 7 grade modified Likert scale) and no more than mild intensity | Brun45 | ||
| Willingness to continue | Willingness to continue maintenance treatment for heartburn with omeprazole or placebo (blinded) | End point analysed according to reason (inadequate relief of heartburn or other reasons) | Venables26 |
| Length of time to acceptable symptom relief | Mean time (in min) up to acceptable symptom relief (no or mild symptoms) after single dose ranitidine treatment for heartburn episodes | Diary card completed during the first hour after each study medication | Elm46 |
| Time to onset of pain relief (VAS <75% of baseline for ⩾30 min) | Electronic diary gave instructions to take medication and provided ratings scales for heartburn at frequent time intervals activated by an alarm clock | Faaij40 | |
| Median time in days for patients to achieve their first 24 hour interval without heartburn | Miner30 | ||
| Symptom scores | Scores calculated by adding daily severity values and multiplying by daily frequency values obtained during each week of symptom recording | A reduction in heartburn score of at least 50% after treatment with omeprazole, compared with placebo treatment, was considered indicative of reflux disease | Fass33 |
| Heartburn scores calculated by multiplying the severity grade (0–3) by the frequency grade (0–3) | Vigneri20 | ||
| Average heartburn severity per day or per night | Heartburn severity scored as 0 = none, 1 = mild, 2 = moderate, 3 = severe | Richter47 | |
| Frequency of heartburn | Percentage of heartburn free days and nights. | Diary card data | Richter48 |
| Mean daily number of heartburn episodes. | Diary card data | Richter29 | |
| Number of days per week with heartburn. | Hatlebakk27 | ||
| Reflux symptoms for less than four consecutive days | Only frequency of symptoms part of the outcome definition—severity of symptoms not defined | Vigneri20 |