There are two ways to determine an mTBI patient's symptoms. One way is to ask patients to talk freely about symptoms and record their spontaneous responses. Another way is to administer a questionnaire that lists the typical symptoms of mTBI, and to ask the patient to check as many as apply.
A recent study found that mTBI patients who completed a symptom questionnaire reported significantly more symptoms than those who were asked to talk freely. A questionnaire that lists the potential problems of mTBI can have advantages-it can be a more exhaustive measure of problems, and it can also help to educate patients who do not understand all the symptoms that might be associated with mTBI.
However, questionnaires may also introduce a "good old days" bias, in which all problems-both pre- and post-injury-are attributed directly to the injury. Patients may also be susceptible to the power of suggestion, and add symptoms on the questionnaire that they would not have otherwise reported freely. Differences between questionnaire and freely reported symptoms are still being researched, but it is suggested that brain injury professionals be vigilant about interviewing patients, regardless of method.
Villemure R, Nolin P, & Le Sage N. Self-reported symptoms during post-mild traumatic brain injury in acute phase: Influence of interviewing method. Brain Injury. (December 2010).