get_lab_data: extract data from the lab test table
In xbsd/rxdsapi2: API for RXDS KDB+ Applications

Description Usage Arguments Details Value Examples

The get_prescriptions family of functions (get_lab_data) provides an interface to query the lab table in the Truven Marketscan Health Research Database. The get_lab_data function extracts data verbatim from the lab table. The get_patient_id_labs function extracts the index date (i.e., the first date of service) corresponding to patient ids (generally the 'enrolid') within the given date range and if applicable, optional parameters.

get_lab_data(optional_q_table_name = "lab_test_results", columns_to_return,
  start, end, optional_lab_codes = "__NULL__",
  optional_abnormal = "__NULL__", optional_enrolids = "__NULL__",
  api_function = "get_lab_data", return_all_flag = F, ...)

get_patient_id_labs(optional_q_table_name = "lab_test_results", start, end,
  optional_lab_codes = "__NULL__", optional_abnormal = "__NULL__",
  optional_enrolids = "__NULL__", return_all_flag = F, ...)

`optional_q_table_name`	an optional field where the name of the prescriptions table may be passed. The function sets a default table name called "prescriptions" which is used when the user does not provide a table name
`columns_to_return`	a character vector of columns names corresponding to the names of the table headers (columns) in the inpatient services table.
`start`	the start date for the query. This should be of the form yyyy.mm.dd and must be passed as a character. For example, to pass June 30, 2017, the value of the start parameter should be "2017.06.30"
`end`	the end date for the query. This should be of the form yyyy.mm.dd and must be passed as a character. For example, to pass Nov. 30, 2017, the value of the start parameter should be "2017.11.30"
`optional_lab_codes`	a character vector of loinccode (lab) codes
`optional_abnormal`	a character value for abnormal indication
`optional_enrolids`	an integer vector of enrolid values
`api_function`	a variable indicating the name of the function. It is unlikely that you'll ever need to change the value of this parameter and it is best left as-is
`return_all_flag`	a boolean value indicating whether all the data should be returned to R. This parameter generally defaults to FALSE since returning large amounts of data to the R Session may take time. It should be set to TRUE only if you are certain that you'd like to load all the data that is a result of the query into your session.
`get_stats`	a boolean variable indicating whether query statistics should be printed

The get_lab_data & get_patient_id_labs functions allow the user to retrieve data from the lab_test_results table in the Truven Health MarketScan® Research Database. The Lab dataset is part of the Truven Health Marketscan's Commercial Claims & Encounters database and contains claims information laboratory tests for patients in the Marketscan database. The table provides information on laboratory tests along with corresponding lab codes. It also contains detailed patient-level demographic data such as age, gender, employment-related information and others on a per-record basis.

Additional Information from Truven: The MarketScan Lab Database helps researchers understand: § How well a drug is performing in the real-world clinical setting § Diagnostic test results administered prior to initiation of drug therapy § Laboratory test results as indicators of drug therapy e effectiveness § Frequency of safety monitoring laboratory tests while a patient is on drug therapy § Differences in treatment patterns between patients whose disease is under control versus not under control The MarketScan Lab Database contains the pooled healthcare experience of over 1 million covered lives, gleaned from sources that include both commercial and Medicare Supplemental coverage. It captures laboratory tests for a subset of the covered lives and mainly represents lab tests ordered in office-based practice. Linkage of lab results to claims supports analyses that are not feasible with claims alone, such as determining effectiveness of treatment, measuring severity of illness, identifying patients for whom treatment may be indicated, and verifying diagnoses recorded on claims.

A data.table with the results of the query

# extract data from prescriptions table

# extract enrolid, svcdate and loinccd (lab code) from prescription drug table between svcdates 2008.01.01 and
# 2008.04.01 for loinccd (Lab) code "2085-9" and enrolid 474702

get_lab_data(columns_to_return=c("enrolid","svcdate","loinccd"),start="2008.01.01",end="2008.04.01",
optional_lab_codes="2085-9",optional_enrolid=474702,return_all_flag=F,get_stats="TRUE")

# extract first svcdate (indexdate) for all patients between svcdates 2008.01.01 and 2008.04.01 for
# lab code "2085-9"
get_patient_id_labs(start="2008.01.01",end="2008.04.01",optional_lab_codes="2085-9",return_all_flag=F,get_stats="TRUE")