How severe is the pain? Measuring migraine with MIDAS

People who want to measure pain are faced with a significant challenge. Subjective bodily sensations must be ‘translated’ so that other people can understand them. This is the only way that the impact on a patient can be measured in a way that allows for categorisation and comparison. How can this be achieved? Doctors have been considering this question for some time. We still do not have the ability to actually share another person’s experience of pain, although it would be extremely helpful to truly understand how their pain feels. It would be useful to have a device with which we could comprehend and categorise the pain.

This challenge also exists in migraine treatment. It is important to find out how severely migraine sufferers are affected by their pain, how the pain develops, and how it can be put in perspective through comparison. This is the only way the severity of the impact caused by headache occurrences can be determined. Moreover, we gain an idea of the course of the illness, allowing measures to be taken which will help the affected person most.

How do you measure the unmeasurable? MIDAS quantifies pain

At the turn of the last millennium, roughly between 1999 and 2001, the doctors Walter Stewart from the USA and Richard Lipton from Great Britain took on this challenge. They decided to develop a data collection device which makes migraine pain measurable. Although experiences of pain are highly individual and differ from person to person, they wanted to be able to make comparisons between the experiences of affected people. The purpose of developing this was also to improve the treatment of individual cases of migraine, by simplifying and standardising the exchange of information between patients and doctors. In this way, they wanted to create a reliable foundation which could be used as a basis for making better decisions on treatment.

It was therefore important to overcome one obstacle: in practice, it is impossible to actually ‘measure’ feelings of pain, as you would with lab results. This is why the developers did not ask any questions about particular feelings of pain. They used the level of impairment that the affected people experienced in everyday life (work, school, studies, leisure time, family) as their measure. This eventually resulted in the so-called ‘MIDAS’ (Migraine Disability Assessment). The MIDAS is a questionnaire and is now the standard tool for measuring the adverse effects that migraine sufferers are exposed to through their pain. Shortly after its introduction, it was already translated into numerous languages and its applicability for the relevant countries was scientifically confirmed.

Measuring the impact step by step: the MIDAS questions

In order to develop an appropriate set of questions, the developers considered particular factors which are seen as very important for migraine sufferers between 20 and 50 years old. In terms of the frequency of migraines and their effects, and with regard to the strain on individuals, this group is particularly severely affected. From this overall picture, they derived five core questions and two additional questions which were meant to show the adverse effects caused by headaches for those impacted by them. The time period from which data on migraine occurrences is collected is three months.

The MIDAS questionnaire asks the following questions:

1. On how many days in the last three months did you not go to work or to school due to your headaches?

2. On how many days in the last three months was your productivity at work or at school reduced by half or more?

3. On how many days in the last three months could you not do any housework due to your headaches?

4. On how many days in the last three months was your productivity at home reduced by half or more?

5. On how many days in the last three months could you not take part in family, social, or leisure activities due to your headaches?

Further questions:

A. On how many days in the last three months did you have headaches?

B. How severe were these headaches? Please rate the intensity of the pain on a scale from 0 – 10 (0 = no pain, 10 = unbearable pain).

The numbers given as answers to questions 1 – 5 are added together to create a total. This is the so-called ‘MIDAS score’. In the evaluation, this is assigned a degree of disability between I and IV, with IV indicating a severe disability.

The additional questions A and B describe the frequency and severity of the attacks. They are not included in the score, but are intended to assist the treating doctor when deciding on appropriate treatment. The survey period of three months is, on the one hand, short enough that the affected people can remember their headache attacks well. On the other hand, 90 days are long enough for the collected data to adequately reflect the occurrence of headaches.

Why the MIDAS has been successful

A number of comprehensive studies were able to show that the MIDAS score reliably illustrates how severely people with migraine are negatively affected by headaches in their lives. Studies in the USA and Great Britain showed: if the total which has been calculated is compared to headache diaries which participants fill out over 90 days, there is good overall consistency. In a further study with doctors from 14 countries, it was shown that the MIDAS results correspond to doctors’ assessments with regard to severity of pain, adverse effects, and the patients’ need for medical treatment. In addition, the doctors attested that the data collection device had very good usability. It is easy to use and to interpret. The worldwide success of the MIDAS has even led to some headache experts now no longer using it only for migraine but also for assessing disability as a result of tension headache.

Measuring pain also improves its prevention

The MIDAS score is particularly good for facilitating the kinds of treatment approaches which take a preventative approach in the mid- to long term. Successful treatments can be measured directly in the form of the reduction of disability and therefore also as an improvement in quality of life. Where we cannot feel another person’s pain, the MIDAS score helps to give us an idea of what this pain means for their everyday life – a relevant measure of personal suffering and a decisive help for headache prevention.