Classification Accuracy and Description of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome in an Integrated Health Care System, 2006-2017. — CFSMEATLAS
Classification Accuracy and Description of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome in an Integrated Health Care System, 2006-2017.
Liles, Elizabeth G, Irving, Stephanie A, Koppolu, Padma et al. · The Permanente journal · 2024 · DOI
Quick Summary
This study looked at how often ME/CFS is diagnosed in a large health care system by checking electronic medical records from 2006 to 2017. Researchers found that while doctors used ME/CFS diagnosis codes for over 500 patients, only about 34% of the cases they reviewed actually matched the real diagnostic criteria for ME/CFS. This shows that relying only on diagnosis codes in medical records can give an inaccurate picture of how many people truly have ME/CFS.
Why It Matters
Accurate diagnosis and prevalence estimates of ME/CFS are critical for understanding disease burden, allocating health care resources, and recognizing patient needs. This study highlights that many patients coded with ME/CFS may not actually meet diagnostic criteria, while the reverse problem—undiagnosed cases—may also exist. These findings underscore the importance of clinical expertise and proper diagnostic criteria application rather than reliance on coding alone.
Observed Findings
Of 188 reviewed records, only 15% were confirmed or probable ME/CFS cases, 19% were possible cases, and 60% did not meet ME/CFS criteria.
Confirmed/probable cases frequently presented with chronic pain (80%) and anxiety/depression (70%).
Only 43% of confirmed/probable cases had completed a sleep study.
The estimated rate of coded ME/CFS cases was 37 per 100,000 population ages 9-39 years.
Diagnosis code rates increased from 2006 to 2017, with the largest absolute increase in the 30-39 age group.
Inferred Conclusions
Using ICD diagnosis codes alone inaccurately estimates ME/CFS incidence and cannot be relied upon for epidemiological surveillance without medical record validation.
Many patients receive ME/CFS diagnosis codes without meeting established clinical criteria, suggesting potential overdiagnosis or misclassification in routine practice.
Improvements in clinician education about diagnostic criteria and better documentation practices are needed to improve diagnostic accuracy.
Remaining Questions
Why do 60% of patients coded with ME/CFS not meet diagnostic criteria—is this due to clinician knowledge gaps, evolving diagnostic criteria, or coding documentation practices?
What This Study Does Not Prove
This study does not prove how many people in the general population actually have ME/CFS, as it only examines patients within one health care system who received diagnosis codes. It does not identify undiagnosed ME/CFS cases in the community or explain why diagnostic accuracy was low (whether due to clinician knowledge gaps, documentation practices, or other factors). The study also cannot establish whether the increasing trend in diagnosis codes reflects true increasing incidence or simply improved coding practices.