R69 - “Illness, unspecified” 

Challenges in Measuring Diagnostic Uncertainty 

Although diagnostic uncertainty is routinely encountered, it is generally poorly defined, poorly understood and therefore not well-quantified in a clinical setting.1In 2017, a systematic review was performed to understand the way diagnostic uncertainty is defined and measured in the medical literature and 123 publications were identified for full review without a single definition of diagnostic uncertainty. Highlighting this significant gap, the authors then proposed a definition of diagnostic uncertainty as a “subjective perception of an inability to provide an accurate explanation of the patient’s health problem.” More recently, another definition was provided as “you wouldn’t be surprised if the patient had a different diagnosis that required a change in management.”2 Prior to these definitions, some attempts to measure diagnostic uncertainty have relied on careful visit note review looking for question marks or language like “maybe,” “unclear,” or “unclear etiology.”3 Estimates using different measures and in different settings range from 11-19% uncertain diagnoses.2,3 More effective use of the ICD-10 code R69 to denote a certain degree of diagnostic uncertainty, would allow more rapid evaluation of how many cases at a given point in time are diagnostically uncertain, “undiagnosed,” “not yet diagnosed,” and/or “illness, unspecified.”

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Diagnostic Uncertainty in Rare Disease Diagnosis 

The path to diagnosis for patients with rare diseases often involve misdiagnoses, delayed diagnosis, missed diagnoses, and conflicting medical opinions.4 As there is difficulty in the process of diagnosis in general, difficulty in defining diagnostic uncertainty and difficulty in the communication of uncertainty to families seeking diagnosis,5 it is reasonable to surmise that these difficulties could be exacerbated in the case of rare diseases likely contributing to lengthy durations to diagnosis. It can take an average of over 6 years to become properly diagnosed with a rare disease and while the “diagnostic odyssey” is well-known to the rare disease community, the costs of this lengthy period of diagnostic uncertainty have only recently been estimated. Delayed diagnoses have been estimated to cost between $87,000-$517,000 in avoidable costs per person in the US.6 In the UK, the total hospital activity levels and costs for rare disease patients 10 years pre-diagnosis were just over double that of a population matched comparator cohort.7 

 

Diagnostic Uncertainty codified by R69 

If a person could have diagnostic uncertainty denoted toward the beginning of their diagnostic odyssey, with sufficient follow-up actions, we could see a reduction in both costs and in time to diagnose rare diseases (and other difficult to diagnose conditions). Such a workflow is not without precedent as in Serbia, if doctors cannot find a proper diagnosis within six months, doctors are obliged to take follow-up action by sending tissue and blood to clinics outside of Serbia.8 

 

Proposed Changes 

We propose the following tabular modifications:

Add the following child codes:

• R69.1 - Provisional diagnosis, illness remains unspecified, not yet diagnosed, or undiagnosed, suspected rare and/or genetic disease. 

• R69.21 - Illness remains unspecified after 2mo

• R69.22 - Illness remains unspecified after 4mo

• R69.23 - Illness remains unspecified after 6mo

• R69.24 - Illness remains unspecified after 9mo

• R69.25 - Illness remains unspecified after 12mo

• R69.26 - Illness remains unspecified after 18mo

• R69.27 - Illness remains unspecified after 2 years

• R69.28 - Illness remains unspecified after 3 years

• R69.29 - Illness remains unspecified after 4 years

• R69.30 - Illness remains unspecified after 5 years

• R69.31 - Illness remains unspecified after 6 years

• R69.32 - Illness remains unspecified after 7 years

• R69.33 - Illness remains unspecified after 8 years

• R69.34 - Illness remains unspecified after 9 years

• R69.35 - Illness remains unspecified after 10 years

• R69.36 - Illness remains unspecified 10 - 14 years

• R69.37 - Illness remains unspecified 15 - 19 years

• R69.38 - Illness remains unspecified 20 - 24 years

• R69.39 - Illness remains unspecified 25 - 29 years

• R69.40 - Illness remains unspecified 30+ years

• R69.41 - Not yet diagnosed - Illness remains unspecified but insufficient diagnostic tools or approaches have been employed

• R69.42 - Not yet diagnosed - illness remains unspecified and there is a lack of clarity regarding whether or not sufficient diagnostic tools or approaches have been employed

• R69.43 - Undiagnosed - Illness remains unspecified after reasonable diagnostic tools or approaches have been employed

• R69.44 - Undiagnosed after full evaluation according to the state of the art 

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• R69.100 - Historically unspecified illness. This code indicates that the timeframe of having an undiagnosed, unspecified, or not yet diagnosed condition has ended. Patients have received an accurate diagnosis.

 

References 

1. Bhise V, Rajan SS, Sittig DF, Morgan RO, Chaudhary P, Singh H. Defining and Measuring Diagnostic Uncertainty in Medicine: A Systematic Review. J Gen Intern Med. 2018;33(1):103-115. 

2. Ipsaro AJ, Patel SJ, Warner DC, et al. Declaring Uncertainty: Using Quality Improvement Methods to Change the Conversation of Diagnosis. Hosp Pediatr. 2021;11(4):334-341. 

3. Whaley LE, Businger AC, Dempsey PP, Linder JA. Visit complexity, diagnostic uncertainty, and antibiotic prescribing for acute cough in primary care: a retrospective study. BMC Fam Pract. 2013;14:120. 

4. Rare Disease Impact Report: Insights from patients and the medical community. Global Genes. https://globalgenes.org/wp-content/uploads/2013/04/ShireReport-1.pdf. Published 04/2013. Accessed 12/2023. 

5. Young EE, Kane J, Timmons K, et al. Brief report: Improving communication of diagnostic uncertainty to families of hospitalized children. Diagnosis (Berl). October 2023. doi:10.1515/dx-2023-0088 

6. Delayed Diagnosis Study. EveryLife Foundation for Rare Diseases. https://everylifefoundation.org/delayed-diagnosis-study/. Published September 5, 2023. Accessed December 1, 2023. 

7. Mendelian, Finding undiagnosed patients early. The Cost of Undiagnosed rare diseases. 

https://www.mendelian.co/blog/the-cost-of-undiagnosed-rare-diseases. Published January 27, 2019. Accessed December 2, 2023. 

8. Adopting Zoja’s law. Center for the Study of Bioethics. https://csb.eu.com/en/events-2015/adopting-zojas-law/. Accessed December 1, 2023. 

9. ICD-10-CM official guidelines for coding and reporting FY 2023 -- UPDATED April 1, 2023 (October 1, 2022 - September 30, 2023). April 2023. https://stacks.cdc.gov/view/cdc/126426. Accessed December 1, 2023.