If you ask a medical doctor what psychometrics is, you might see a blank stare.
Yet Chih-Hung Chang, an associate professor at Northwestern University Feinberg School of Medicine, said he thinks patient diagnosis and treatment would benefit from having this type of quantitative psychology become common practice in medicine. He talks about how people-reported data, electronic devices and data analysis could bring about more holistic patient care.
Q: What is psychometrics?
A: It’s basically one of the disciplines of psychology which has more of a focus on numbers. The important thing about psychometrics is it converts latent, unobservable traits into numbers and uses those numbers for comparisons.
Psychometrics actually has to do mostly with how to design good assessment tools. Without the tools, the numbers you get from the responses of the patients might be meaningless. So psychometrics uses a lot of statistical modeling in order to determine whether this ‘good’ assessment tool could be applied to different populations.
Q: What’s the story behind this science?
A: It actually was originally developed for educational testing or psychological measurement, but I think it is mostly applied to do personality assessment. For instance, if you want to measure people’s depression or their anxiety or some other psychological trait, you use a questionnaire or test items. Ask them a list of items, and based on their responses, you create a score and then create a profile to compare [them] to ‘normal people.’
Right now most of the instruments have been developed for assessing health-related quality of life. Researchers or clinicians could use those numbers to understand whether [patients] need further treatment or a referral to a specialist.
Q: How does psychometrics help doctors see patients more holistically?
A: Most of the instruments are capturing mental health, physical health, social health and, sometimes, spiritual health. [Psychometricians are] making sure that the whole picture of the patient can be profiled with some numbers so that the treating physician could utilize that information and decide what might be the best treatment options available.
Q: How do computers and the Internet assist you in this process?
A: Using large databases, you compare your patient’s characteristics to the [patients in the] large database. You know with his characteristics, he might be more likely to benefit from one specific treatment. You could also integrate laboratory data or some other clinical data utilizing electronic medical records. So you compare [all] that in real time.
You sort of have an integrated system: from the patient’s perspective, from the clinician’s perspective, from data’s viewpoint. And you generate a report specifically tailored to that particular patient, so clinicians could utilize that printout or chart.
Q: Is the ultimate goal for patients to use their smartphones, tablets and other electronic devices even while they’re healthy in order to improve their future doctor visits?
A: The overall goal is to allow the use of technology so that patients could enter their information. That information gets analyzed and summarized and delivered to a treating physician to sort of open up the communication channel.
It sounds simple but you want to make sure that information that gets entered is valid and reliable because sometimes a patient or some other people [such as caretakers of incapacitated individuals] might try to report data that is not valid.
We build in some validation questions in the questionnaire, so we could sort of detect whether that person is responding inconsistently. For instance, if you respond ‘very much’ to most of the questions but you respond ‘not at all’ to one of the related questions, we know there must be something going on. And then we could detect whether the person is lying or making the responses up.
Q: Don’t we already have health-related apps like ones that measure body mass index and fiber intake?
A: We do, but in order to provide a holistic picture of the patient, not only do you have to report some of the daily indicators like vital signs, [but] you also need to use some of the tools, like measuring particular aspects related to quality of life.
Q: How could psychometrics help a patient’s treatment and diagnosis?
A: Once clinicians utilize this tool, with the information provided to them, they could spend their time more efficiently. They could try to target the area or the problems from the patients’ [perspective].
Clinicians need to spend a lot of time trying to deal with issues and problems, but time is always a concern. With this type of information presented to them with the patient’s condition, they could use that information to sort of facilitate their communication and to make more informed decisions.