icd9 (version 1.1)

icd9WideToLong: convert ICD data from wide to long format

Description

This is different enough to dcast in reshape2 that it needs writing again specifically for ICD codes. This function packages the core reshape function. Empty strings and NA values will be dropped, and everything else kept. No validation of the ICD codes is done.

Usage

icd9WideToLong(x, visitId = NULL, icdLabels = NULL, icdName = "icdCode")

Arguments

x

data.frame in wide format, i.e. one row per patient, and multiple columns containing ICD codes, empty strings or NA.

visitId

The name of the column in the data frame which contains the patient or visit identifier. Typically this is the visit identifier, since patients come leave and enter hospital with different ICD-9 codes. It is a character vector of length one. Defaults to "visitId"

icdLabels

vector of column names in which codes are found. If NULL, all columns matching icd or ICD will be included.

icdName

character vector length one containing the new column name for the ICD codes, defaults to "icdCode"

Value

data frame with visitId column named the same as input, and a column named by icd.name containing all the non-NA and non-empty codes found in the wide input data.

See Also

Other ICD-9 convert: convert, convert, icd9DecimalToParts, icd9DecimalToShort, icd9GetMajor, icd9MajMinToCode, icd9MajMinToDecimal, icd9MajMinToParts, icd9MajMinToShort, icd9PartsToDecimal, icd9PartsToShort, icd9ShortToDecimal, icd9ShortToParts; icd9ChaptersToMap; icd9DropLeadingZeroes, icd9DropLeadingZeroesDecimal, icd9DropLeadingZeroesMajor, icd9DropLeadingZeroesShort; icd9LongToWide

Examples

# NOT RUN {
widedf <- data.frame(visitId = c("a", "b", "c"),
    icd9_01 = c("441", "4424", "441"),
    icd9_02 = c(NA, "443", NA))
  icd9WideToLong(widedf)
# }