Retrieve a copy of the internal lookup table for all known ICD codes.
Value
a data.frame
The default return has the following columns:
icdv: Integer vector indicating if the code is from ICD-9 or ICD-10dx: Integer vector. 1 if the code is a diagnostic, (ICD-9-CM, ICD-10-CM, WHO, CDC Mortality), or 0 if the code is procedural (ICD-9-PCS, ICD-10-PCS)full_code: Character vector with the ICD code and any relevant decimal pointcode: Character vector with the compact ICD code omitting any relevant decimal pointsrc: Character vector reporting the source of the information. See Details.known_start: Integer vector reporting the first known year of use. See Details.known_end: Integer vector reporting the last known year of use. See Details.assignable_start: Integer vector reporting the first known year the code was assignable. See Details.assignable_end: Integer vector reporting the last known year the code was assignable. See Details.
When with.descriptions = TRUE there are the following additional columns:
desc: Character vector of descriptions. Forcmscodes descriptions from CMS are used preferentially over CDC.desc_start: Integer vector of the first year the description was used.desc_end: Integer vector of the last year the description was used.
When with.hierarchy = TRUE there are the following additional columns:
chaptersubchaptercategorysubcategorysubclassificationsubsubclassificationextension
Details
Sources
There are three sources of ICD codes.
cms: Codes from the ICD-9-CM, ICD-9-PCS, ICD-10-CM, and ICD-10-PCS standards.who: Codes from World Health Organization.cdc: Codes from CDC Mortality coding standard.
Fiscal and Calendar Years
When reporting years there is a mix of fiscal and calendar years.
Fiscal years are the United States Federal Government fiscal years, running from October 1 to September 30. For example, fiscal year 2013 started October 1 2012 and ended on September 30 2013.
Calendar years run January 1 to December 31.
Within the ICD data there are columns
known_start, known_end, assignable_start, assignable_end,
desc_start and desc_end. For ICD codes with src == "cms", these are
fiscal years. For codes with src == "cdc" or src == "who" these are
calendar years.
known_start is the first fiscal or calendar year (depending on source) that
the medicalcoder package as definitive source data for. ICD-9-CM started in
the United States in fiscal year 1980. The CDC extracts included in
medicalcoder span fiscal years 1997–2012; the CMS ICD-9-CM/PCS extracts
start in fiscal year 2006 and run through fiscal year 2015. As such 1997 is
the earliest "known start" for ICD-9 within medicalcoder.
known_end is the last fiscal or calendar year (depending on source)
for which we have definitive source data for. For ICD-9-CM and ICD-9-PCS,
CMS provides data through fiscal year 2015, while the CDC extracts stop at
fiscal year 2012. For ICD-10-CM and ICD-10-PCS, which are active, it is just
the last year of known data. ICD-10 from the WHO ends in 2019.
Header and Assignable Codes
"Assignable" indicates that the code is the most granular for the source.
Ideally codes are reported with the greatest level of detail but that is not
always the case. Also, the greatest level of detail can differ between
sources.
Example: C86 is a header code for cms and who because codes C86.0, C86.1,
C86.2, C86.3, C86.4, C86.5, and C86.6 all exist in both standards. No code
with a fifth digit exists in the who so all these four digit codes are
'assignable.' In the cms standard, C86.0 was assignable through fiscal
year 2024. In fiscal year 2025 codes C86.00 and C86.01 were added making
C86.0 a header code and C86.00 and C86.01 assignable codes.
Examples
icd_codes <- get_icd_codes()
str(icd_codes)
#> 'data.frame': 249736 obs. of 9 variables:
#> $ icdv : int 9 9 9 9 9 9 9 9 9 9 ...
#> $ dx : int 0 0 0 0 0 0 0 0 0 0 ...
#> $ full_code : chr "00" "00" "00.0" "00.0" ...
#> $ code : chr "00" "00" "000" "000" ...
#> $ src : chr "cdc" "cms" "cdc" "cms" ...
#> $ known_start : int 2003 2006 2003 2006 2003 2006 2003 2006 2003 2006 ...
#> $ known_end : int 2012 2015 2012 2015 2012 2015 2012 2015 2012 2015 ...
#> $ assignable_start: int NA NA NA NA 2003 2006 2003 2006 2003 2006 ...
#> $ assignable_end : int NA NA NA NA 2012 2015 2012 2015 2012 2015 ...
# Explore the change in the assignable year for C86 code between CMS and
# WHO
subset(get_icd_codes(), grepl("^C86$", full_code))
#> icdv dx full_code code src known_start known_end assignable_start
#> 128357 10 1 C86 C86 cms 2014 2026 NA
#> 128358 10 1 C86 C86 who 2010 2019 NA
#> assignable_end
#> 128357 NA
#> 128358 NA
subset(get_icd_codes(), grepl("^C86\\.\\d$", full_code))
#> icdv dx full_code code src known_start known_end assignable_start
#> 128359 10 1 C86.0 C860 cms 2014 2026 2014
#> 128360 10 1 C86.0 C860 who 2010 2019 2010
#> 128363 10 1 C86.1 C861 cms 2014 2026 2014
#> 128364 10 1 C86.1 C861 who 2010 2019 2010
#> 128367 10 1 C86.2 C862 cms 2014 2026 2014
#> 128368 10 1 C86.2 C862 who 2010 2019 2010
#> 128371 10 1 C86.3 C863 cms 2014 2026 2014
#> 128372 10 1 C86.3 C863 who 2010 2019 2010
#> 128375 10 1 C86.4 C864 cms 2014 2026 2014
#> 128376 10 1 C86.4 C864 who 2010 2019 2010
#> 128379 10 1 C86.5 C865 cms 2014 2026 2014
#> 128380 10 1 C86.5 C865 who 2010 2019 2010
#> 128383 10 1 C86.6 C866 cms 2014 2026 2014
#> 128384 10 1 C86.6 C866 who 2010 2019 2010
#> assignable_end
#> 128359 2024
#> 128360 2019
#> 128363 2024
#> 128364 2019
#> 128367 2024
#> 128368 2019
#> 128371 2024
#> 128372 2019
#> 128375 2024
#> 128376 2019
#> 128379 2024
#> 128380 2019
#> 128383 2024
#> 128384 2019
subset(get_icd_codes(), grepl("^C86\\.0(\\d|$)", full_code))
#> icdv dx full_code code src known_start known_end assignable_start
#> 128359 10 1 C86.0 C860 cms 2014 2026 2014
#> 128360 10 1 C86.0 C860 who 2010 2019 2010
#> 128361 10 1 C86.00 C8600 cms 2025 2026 2025
#> 128362 10 1 C86.01 C8601 cms 2025 2026 2025
#> assignable_end
#> 128359 2024
#> 128360 2019
#> 128361 2026
#> 128362 2026
is_icd("C86", headerok = FALSE) # FALSE
#> [1] FALSE
is_icd("C86", headerok = TRUE) # TRUE
#> [1] TRUE
is_icd("C86", headerok = TRUE, src = "cdc") # Not a CDC mortality code
#> [1] FALSE
lookup_icd_codes("^C86\\.0\\d*", regex = TRUE)
#> input_regex match_type icdv dx full_code code src known_start known_end
#> 1 ^C86\\.0\\d* full_code 10 1 C86.0 C860 cms 2014 2026
#> 2 ^C86\\.0\\d* full_code 10 1 C86.0 C860 who 2010 2019
#> 5 ^C86\\.0\\d* full_code 10 1 C86.00 C8600 cms 2025 2026
#> 6 ^C86\\.0\\d* full_code 10 1 C86.01 C8601 cms 2025 2026
#> assignable_start assignable_end
#> 1 2014 2024
#> 2 2010 2019
#> 5 2025 2026
#> 6 2025 2026