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Summary

Lifecycle: draftEditUnder review
What this benchmark means
README.md

Public entries: Python and R. Passing coverage requires an installed inventory.

Goal: flag the last laboratory record collected on or before first exposure for each subject, test, and specimen: LBLOBXFL.

Input: long-form Operational Data Model (ODM) data with one row per collected item: a laboratory result, its collection date, or its completion status. A small test dictionary (lb_mapping.csv) translates result items into test codes and specimens. One demographics row per subject carries the reference start date (first exposure).

Variables:

  • LBTESTCD is the test code from the item dictionary; together with the specimen it defines the series the flag is assigned within.
  • LBSPEC is the specimen from the item dictionary; a test measured in more than one specimen is flagged separately per specimen.
  • LBORRES is the result as collected; missing on records that were not done.
  • LBDTC is the collection date as collected.
  • LBSTAT is the completion status as collected; NOT DONE on records without a result.
  • LBLOBXFL is Y on the latest record with a result whose collection date falls on or before the subject's reference start date; blank on every other record.

Note: records without a result never carry the flag, even when they carry the latest date. A subject with no reference start date has the flag on the latest record with a result, since no record falls after exposure. Dates compare at day precision, so a record collected on the day of first exposure still qualifies; of two results collected on the same date, the one with the higher sequence number (LBSEQ) is flagged.

Inputs

Under review
3 source files

input/dm.csv

Edit
2 rows
input/dm.csv
STUDYIDUSUBJIDRFSTDTC
YAMAA-012026-01-15
YAMAA-01—

input/lb_mapping.csv

Edit
4 rows
input/lb_mapping.csv
ItemOIDLBTESTCDLBSPEC
IT.LB.ALT_SERUMALTSERUM
IT.LB.GLUC_SERUMGLUCSERUM
IT.LB.K_SERUMKSERUM
IT.LB.K_URINEKURINE

input/odm.csv

Edit
29 rows
input/odm.csv
StudyOIDMetaDataVersionOIDSubjectKeyStudyEventOIDStudyEventRepeatKeyFormOIDFormRepeatKeyItemGroupOIDItemGroupRepeatKeyItemOIDValue
YAMAA-01MDV.1YAMAA-01-101SE.LB1FO.LB1IG.LB1IT.LB.LBDTC2026-01-05
YAMAA-01MDV.1YAMAA-01-101SE.LB1FO.LB1IG.LB1IT.LB.ALT_SERUM32
YAMAA-01MDV.1YAMAA-01-101SE.LB1FO.LB1IG.LB2IT.LB.LBDTC2026-01-10
YAMAA-01MDV.1YAMAA-01-101SE.LB1FO.LB1IG.LB2IT.LB.ALT_SERUM35
YAMAA-01MDV.1YAMAA-01-101SE.LB1FO.LB1IG.LB3IT.LB.LBDTC2026-01-14
YAMAA-01MDV.1YAMAA-01-101SE.LB1FO.LB1IG.LB3IT.LB.ALT_SERUM—
YAMAA-01MDV.1YAMAA-01-101SE.LB1FO.LB1IG.LB3IT.LB.LBSTATNOT DONE
YAMAA-01MDV.1YAMAA-01-101SE.LB1FO.LB1IG.LB4IT.LB.LBDTC2026-01-15
YAMAA-01MDV.1YAMAA-01-101SE.LB1FO.LB1IG.LB4IT.LB.ALT_SERUM38
YAMAA-01MDV.1YAMAA-01-101SE.LB1FO.LB1IG.LB5IT.LB.LBDTC2026-01-20
YAMAA-01MDV.1YAMAA-01-101SE.LB1FO.LB1IG.LB5IT.LB.ALT_SERUM40
YAMAA-01MDV.1YAMAA-01-101SE.LB1FO.LB1IG.LB6IT.LB.LBDTC2026-01-08
YAMAA-01MDV.1YAMAA-01-101SE.LB1FO.LB1IG.LB6IT.LB.GLUC_SERUM5.1
YAMAA-01MDV.1YAMAA-01-101SE.LB1FO.LB1IG.LB7IT.LB.LBDTC2026-01-16
YAMAA-01MDV.1YAMAA-01-101SE.LB1FO.LB1IG.LB7IT.LB.GLUC_SERUM5.4
YAMAA-01MDV.1YAMAA-01-101SE.LB1FO.LB1IG.LB8IT.LB.LBDTC2026-01-09
YAMAA-01MDV.1YAMAA-01-101SE.LB1FO.LB1IG.LB8IT.LB.K_SERUM4.2
YAMAA-01MDV.1YAMAA-01-101SE.LB1FO.LB1IG.LB9IT.LB.LBDTC2026-01-18
YAMAA-01MDV.1YAMAA-01-101SE.LB1FO.LB1IG.LB9IT.LB.K_SERUM4.5
YAMAA-01MDV.1YAMAA-01-101SE.LB1FO.LB1IG.LB10IT.LB.LBDTC2026-01-12
YAMAA-01MDV.1YAMAA-01-101SE.LB1FO.LB1IG.LB10IT.LB.K_URINE60
YAMAA-01MDV.1YAMAA-01-101SE.LB1FO.LB1IG.LB11IT.LB.LBDTC2026-01-14
YAMAA-01MDV.1YAMAA-01-101SE.LB1FO.LB1IG.LB11IT.LB.K_URINE62
YAMAA-01MDV.1YAMAA-01-102SE.LB1FO.LB1IG.LB12IT.LB.LBDTC2026-02-01
YAMAA-01MDV.1YAMAA-01-102SE.LB1FO.LB1IG.LB12IT.LB.ALT_SERUM30
YAMAA-01MDV.1YAMAA-01-102SE.LB1FO.LB1IG.LB13IT.LB.LBDTC2026-02-10
YAMAA-01MDV.1YAMAA-01-102SE.LB1FO.LB1IG.LB13IT.LB.ALT_SERUM33
YAMAA-01MDV.1YAMAA-01-102SE.LB1FO.LB1IG.LB14IT.LB.LBDTC2026-02-10
YAMAA-01MDV.1YAMAA-01-102SE.LB1FO.LB1IG.LB14IT.LB.ALT_SERUM34

Expected output

Under review
14 expected rows

expected/lb.csv

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14 rows
expected/lb.csv
DOMAINSTUDYIDUSUBJIDLBSEQLBTESTCDLBSPECLBORRESLBDTCLBSTATLBLOBXFL
LBYAMAA-011ALTSERUM322026-01-05——
LBYAMAA-012ALTSERUM352026-01-10——
LBYAMAA-013ALTSERUM—2026-01-14NOT DONE—
LBYAMAA-014ALTSERUM382026-01-15—Y
LBYAMAA-015ALTSERUM402026-01-20——
LBYAMAA-016GLUCSERUM5.12026-01-08—Y
LBYAMAA-017GLUCSERUM5.42026-01-16——
LBYAMAA-018KSERUM4.22026-01-09—Y
LBYAMAA-019KSERUM4.52026-01-18——
LBYAMAA-0110KURINE602026-01-12——
LBYAMAA-0111KURINE622026-01-14—Y
LBYAMAA-0112ALTSERUM302026-02-01——
LBYAMAA-0113ALTSERUM332026-02-10——
LBYAMAA-0114ALTSERUM342026-02-10—Y
Shaded columns are derived— = missing value

Human review and assessment

Your review

3 questions and your comments · View benchmark discussions

Mapping spec

Generated from the benchmark YAML; do not edit by hand

Variable NameVariable LabelTypeLengthControlled Terms or FormatOriginCoreConversion DefinitionVariable TypeVariable OrderComments for Define
DOMAINDomain AbbreviationCharAssignedSet constant value "LB".SDTM1
STUDYIDStudy IdentifierCharCollectedCopy value from ODM.StudyOID.SDTM2
USUBJIDUnique Subject IdentifierCharCollectedCopy value from ODM.SubjectKey.SDTM3
LBSEQSequence NumberNumCollectedCopy value from ODM.ItemGroupRepeatKey.SDTM4
LBTESTCDLab Test or Examination Short NameCharDerivedSet per constructed row; see the Row construction sheet.SDTM5
LBSPECSpecimen Material TypeCharDerivedSet per constructed row; see the Row construction sheet.SDTM6
LBORRESResult or Finding in Original UnitsCharDerivedSet per constructed row; see the Row construction sheet.SDTM7
LBDTCDate/Time of Specimen CollectionCharISO 8601CollectedRead collected ODM item IT.LB.LBDTC; no identified record yields blank.SDTM8
LBSTATCompletion StatusCharCollectedRead collected ODM item IT.LB.LBSTAT; no identified record yields blank.SDTM9
LBLOBXFLLast Observation Before Exposure FlagCharDerived"Y" when LOBXRNK = 1; blank otherwise.SDTM10
TemplateInclude whenLBTESTCDLBSPECLBORRES
lb_resultLBTESTCD IS NOT NULLCopy LBTESTCD from the LB_MAPPING record whose ItemOID equals ODM.ItemOID, and no match yields blankCopy LBSPEC from the LB_MAPPING record whose ItemOID equals ODM.ItemOID, and no match yields blankAggregate ONLY(ODM.Value) over records matching on the shared output keys
VersionDateAuthorDescriptionReviewerSign-off
1.72026-10-20yamaa docs buildRead a specification in the 1.0 surface as its 0.5 counterpart; state that missing values stay missing where a mapping declares no missing handler, and leave out a declared missing answer that restates a handler's default
1.62026-10-17yamaa docs buildDescribe collected date parts written as ISO 8601 date text and times of day counted in seconds since midnight
1.52026-10-17yamaa docs buildName collected precision in words instead of letter codes; state imputation fallbacks, minimum source precision, bounds ignored outside the collected period, and invalid text with no handler as an error; describe date and datetime shifts, imputation flag codes, and partial text giving no date part
1.42026-10-15yamaa docs buildState datetime precision codes through the hour and minute, and complete only the time parts a collected datetime lacks
1.32026-09-29yamaa docs buildShow study codelist names, external dictionaries, and ISO 8601 formats in variable rows; list the document's codelist values and metadata
1.22026-09-29yamaa docs buildClassify ADaM copies from a declared input as Predecessor and recodes as Derived, and SDTM recodes of locally derived columns as Derived
1.12026-09-29yamaa docs buildResolve lookups into the donor record they select, and give every derivation shape a plain-language rule instead of its raw YAML
1.0yamaa docs buildInitial generation from spec.yaml

Agent prompt

The request an agent receives with the input files; each tier states no more than the one above

prompts/sdtm-lb-last-observation-before-exposure/full.md

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30 lines

Following CDISC SDTM standards, use the provided DM, LB_MAPPING, and ODM datasets to create an LB dataset with one record per laboratory result.

The output dataset should contain the following columns in this order: DOMAIN, STUDYID, USUBJID, LBSEQ, LBTESTCD, LBSPEC, LBORRES, LBDTC, LBSTAT, LBLOBXFL

DOMAIN is "LB". STUDYID is the study OID in ODM, as given, and USUBJID is the subject key in ODM, as given. LBSEQ is the item group repeat number of the result, as collected. LBTESTCD is the test code in LB_MAPPING for the result item, and LBSPEC is the specimen in LB_MAPPING for that item. LBTESTCD and LBSPEC together define the series within which the flag is assigned, and a test measured in more than one specimen is flagged separately for each specimen. LBORRES is the result as collected, and has no value on a record that was not done. LBDTC is the collection date as collected. LBSTAT is the completion status as collected, "NOT DONE" on a record without a result. LBLOBXFL is "Y" on the latest record with a result in the series whose collection date falls on or before the subject's reference start date in DM, and has no value on every other record. A record without a result never carries the flag, even when it carries the latest date. A subject with no reference start date has the flag on the latest record with a result, since no record falls after exposure. Dates compare at day precision, so a record collected on the day of the reference start date still qualifies. Of two results collected on the same date, the one with the higher LBSEQ carries the flag.

Read the source datasets from /app/input and save the completed dataset as /app/output/lb.csv.

prompts/sdtm-lb-last-observation-before-exposure/conventions.md

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11 lines

Following CDISC SDTM standards, use the provided DM, LB_MAPPING, and ODM datasets to create an LB dataset with one record per laboratory result.

The output dataset should contain the following columns in this order: DOMAIN, STUDYID, USUBJID, LBSEQ, LBTESTCD, LBSPEC, LBORRES, LBDTC, LBSTAT, LBLOBXFL

DOMAIN is "LB". LBLOBXFL is "Y" or has no value.

Read the source datasets from /app/input and save the completed dataset as /app/output/lb.csv.

prompts/sdtm-lb-last-observation-before-exposure/brief.md

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9 lines

Following CDISC SDTM standards, use the provided DM, LB_MAPPING, and ODM datasets to create an LB dataset with one record per laboratory result.

The output dataset should contain the following columns in this order: DOMAIN, STUDYID, USUBJID, LBSEQ, LBTESTCD, LBSPEC, LBORRES, LBDTC, LBSTAT, LBLOBXFL

Read the source datasets from /app/input and save the completed dataset as /app/output/lb.csv.

yamaa code

Public calls generated from benchmark.yaml; results must match the expected output

R

Edit
3 lines
library(yamaa)yamaa_spec("spec.yaml")$run()$output

Python

Edit
3 lines
import yamaayamaa.spec("spec.yaml").run().output

Solution without yamaa

Written from the full prompt and the inputs alone; CI checks it reproduces the expected output

solutions/sdtm-lb-last-observation-before-exposure/result.R

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88 lines
# Reference solution for the yamaa benchmark sdtm-lb-last-observation-before-exposure (R track).## Written from the benchmark's full prompt and its inputs alone, as an agent# would write it. Harbor's oracle agent runs it to check that the prompt can# be solved and that the grader scores a correct answer 1.library(dplyr, warn.conflicts = FALSE)library(readr)library(purrr)odm <- read_csv(  "/app/input/odm.csv",  col_types = cols(.default = col_character())) |>  mutate(Value = na_if(Value, ""))dm <- read_csv(  "/app/input/dm.csv",  col_types = cols(.default = col_character())) |>  mutate(RFSTDTC = na_if(RFSTDTC, ""))mapping <- read_csv(  "/app/input/lb_mapping.csv",  col_types = cols(.default = col_character()))groups <- odm |>  distinct(StudyOID, SubjectKey, ItemGroupRepeatKey)one_group <- function(study, subj, igrep) {  sub <- odm |>    filter(SubjectKey == subj, ItemGroupRepeatKey == igrep)  get <- function(oid) {    hit <- sub |> filter(ItemOID == oid)    if (nrow(hit) == 0) return(NA_character_)    hit$Value[[1]]  }  lbdtc <- get("IT.LB.LBDTC")  found <- mapping |>    filter(ItemOID %in% sub$ItemOID) |>    slice_head(n = 1)  if (nrow(found) == 0) return(tibble())  raw <- get(found$ItemOID[[1]])  has_result <- !is.na(raw)  tibble(    DOMAIN = "LB",    STUDYID = study,    USUBJID = subj,    LBSEQ = as.integer(igrep),    LBTESTCD = found$LBTESTCD[[1]],    LBSPEC = found$LBSPEC[[1]],    LBORRES = raw,    LBDTC = lbdtc,    LBSTAT = if_else(has_result, NA_character_, "NOT DONE"),    HAS = has_result  )}lb <- pmap_dfr(  list(groups$StudyOID, groups$SubjectKey, groups$ItemGroupRepeatKey),  one_group)flags <- lb |>  filter(HAS, !is.na(LBDTC)) |>  left_join(dm |> select(USUBJID, RFSTDTC), by = "USUBJID") |>  mutate(DAYDATE = substr(LBDTC, 1, 10), REFDAY = substr(RFSTDTC, 1, 10)) |>  filter(is.na(REFDAY) | DAYDATE <= REFDAY) |>  arrange(USUBJID, LBTESTCD, LBSPEC, DAYDATE, LBSEQ) |>  group_by(USUBJID, LBTESTCD, LBSPEC) |>  slice_tail(n = 1) |>  ungroup() |>  transmute(USUBJID, LBTESTCD, LBSPEC, FLAGSEQ = LBSEQ)lb <- lb |>  left_join(flags, by = c("USUBJID", "LBTESTCD", "LBSPEC")) |>  mutate(    LBLOBXFL = if_else(HAS & !is.na(FLAGSEQ) & LBSEQ == FLAGSEQ, "Y", NA_character_)  ) |>  arrange(STUDYID, USUBJID, LBSEQ) |>  select(    DOMAIN, STUDYID, USUBJID, LBSEQ, LBTESTCD, LBSPEC, LBORRES,    LBDTC, LBSTAT, LBLOBXFL  )dir.create("/app/output", showWarnings = FALSE)write_csv(lb, "/app/output/lb.csv", na = "")

solutions/sdtm-lb-last-observation-before-exposure/result.py

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137 lines
# Reference solution for the yamaa benchmark sdtm-lb-last-observation-before-exposure (Python track).## Written from the benchmark's full prompt and its inputs alone, as an agent# would write it. Harbor's oracle agent runs it to check that the prompt can# be solved and that the grader scores a correct answer 1."""Build the LB dataset from DM, LB_MAPPING and ODM extracts.One output record per laboratory result item group in the ODM extract.LBLOBXFL flags the last observation with a result, within each(LBTESTCD, LBSPEC) series for a subject, whose collection date falls onor before the subject's reference start date (RFSTDTC in DM). A subjectwithout a reference start date has the flag on the latest record with aresult in the series."""import csvfrom datetime import dateINPUT_DIR = "/app/input"OUTPUT_FILE = "/app/output/lb.csv"COLUMNS = [    "DOMAIN",    "STUDYID",    "USUBJID",    "LBSEQ",    "LBTESTCD",    "LBSPEC",    "LBORRES",    "LBDTC",    "LBSTAT",    "LBLOBXFL",]def read_csv(path):    with open(path, newline="", encoding="utf-8") as handle:        return list(csv.DictReader(handle))def day(text):    """Parse an ISO date/datetime at day precision; None when blank."""    text = (text or "").strip()    if not text:        return None    return date.fromisoformat(text[:10])def main():    dm = read_csv(f"{INPUT_DIR}/dm.csv")    mapping = read_csv(f"{INPUT_DIR}/lb_mapping.csv")    odm = read_csv(f"{INPUT_DIR}/odm.csv")    ref_start = {}    for row in dm:        ref_start[row["USUBJID"]] = day(row["RFSTDTC"])    test_map = {row["ItemOID"]: (row["LBTESTCD"], row["LBSPEC"]) for row in mapping}    # Group the ODM items into one record per item group occurrence,    # keeping the collected order.    groups = {}    order = []    for row in odm:        key = (row["StudyOID"], row["SubjectKey"], row["ItemGroupRepeatKey"])        if key not in groups:            groups[key] = {                "STUDYID": row["StudyOID"],                "USUBJID": row["SubjectKey"],                "LBSEQ": row["ItemGroupRepeatKey"],                "items": {},            }            order.append(key)        groups[key]["items"][row["ItemOID"]] = row["Value"]    records = []    for key in order:        group = groups[key]        items = group["items"]        result_items = [oid for oid in items if oid in test_map]        if not result_items:            continue        item_oid = result_items[0]        testcd, spec = test_map[item_oid]        result = (items.get(item_oid) or "").strip()        stat = (items.get("IT.LB.LBSTAT") or "").strip()        if not result:            stat = stat or "NOT DONE"        records.append(            {                "DOMAIN": "LB",                "STUDYID": group["STUDYID"],                "USUBJID": group["USUBJID"],                "LBSEQ": group["LBSEQ"],                "LBTESTCD": testcd,                "LBSPEC": spec,                "LBORRES": result,                "LBDTC": (items.get("IT.LB.LBDTC") or "").strip(),                "LBSTAT": stat,                "LBLOBXFL": "",            }        )    # Assign the flag within each subject and (test, specimen) series.    series = {}    for idx, record in enumerate(records):        key = (record["USUBJID"], record["LBTESTCD"], record["LBSPEC"])        series.setdefault(key, []).append(idx)    for (usubjid, _testcd, _spec), idxs in series.items():        ref = ref_start.get(usubjid)        candidates = []        for idx in idxs:            record = records[idx]            if not record["LBORRES"]:                continue  # a record without a result never carries the flag            collected = day(record["LBDTC"])            if ref is not None and (collected is None or collected > ref):                continue  # collected after the reference start date            candidates.append(idx)        if not candidates:            continue        best = max(            candidates,            key=lambda i: (day(records[i]["LBDTC"]) or date.min, int(records[i]["LBSEQ"])),        )        records[best]["LBLOBXFL"] = "Y"    with open(OUTPUT_FILE, "w", newline="", encoding="utf-8") as handle:        writer = csv.DictWriter(handle, fieldnames=COLUMNS)        writer.writeheader()        writer.writerows(records)if __name__ == "__main__":    main()

solutions/sdtm-lb-last-observation-before-exposure/result.sas

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48 lines
/* opensas reference solution for the yamaa benchmark sdtm-lb-last-observation-before-exposure.   Reads the benchmark inputs and derives the requested output.   Execute with the existing opensas runtime: opensas /app/output/result.sas. */data dm;  length STUDYID USUBJID RFSTDTC $1024;  infile "/app/input/dm.csv" dsd dlm="," firstobs=2 truncover lrecl=32767;  input STUDYID : $char1024. USUBJID : $char1024. RFSTDTC : $char1024.;run;data lb_mapping;  length ItemOID LBTESTCD LBSPEC $1024;  infile "/app/input/lb_mapping.csv" dsd dlm="," firstobs=2 truncover lrecl=32767;  input ItemOID : $char1024. LBTESTCD : $char1024. LBSPEC : $char1024.;run;data odm;  length StudyOID MetaDataVersionOID SubjectKey StudyEventOID StudyEventRepeatKey FormOID FormRepeatKey ItemGroupOID ItemGroupRepeatKey ItemOID Value $1024;  infile "/app/input/odm.csv" dsd dlm="," firstobs=2 truncover lrecl=32767;  input StudyOID : $char1024. MetaDataVersionOID : $char1024. SubjectKey : $char1024. StudyEventOID : $char1024. StudyEventRepeatKey : $char1024. FormOID : $char1024. FormRepeatKey : $char1024. ItemGroupOID : $char1024. ItemGroupRepeatKey : $char1024. ItemOID : $char1024. Value : $char1024.;run;proc sort data=odm out=ordered; by StudyOID SubjectKey StudyEventOID StudyEventRepeatKey FormOID FormRepeatKey ItemGroupRepeatKey; run;data dates;  length LBDTC LBSTAT $1024;  retain LBDTC LBSTAT;  set ordered;  by StudyOID SubjectKey StudyEventOID StudyEventRepeatKey FormOID FormRepeatKey ItemGroupRepeatKey;  if first.ItemGroupRepeatKey then do;    LBDTC=''; LBSTAT='';  end;    if ItemOID='IT.LB.LBDTC' then LBDTC=Value;  if ItemOID='IT.LB.LBSTAT' then LBSTAT=Value;  if last.ItemGroupRepeatKey then output;run;proc sql;create table joined as select a.*,b.LBDTC,b.LBSTAT,c.LBTESTCD,c.LBSPEC,d.RFSTDTC from odm a inner join dates b on a.StudyOID=b.StudyOID and a.SubjectKey=b.SubjectKey and a.StudyEventOID=b.StudyEventOID and a.StudyEventRepeatKey=b.StudyEventRepeatKey and a.FormOID=b.FormOID and a.FormRepeatKey=b.FormRepeatKey and a.ItemGroupRepeatKey=b.ItemGroupRepeatKey inner join lb_mapping c on a.ItemOID=c.ItemOID left join dm d on a.StudyOID=d.STUDYID and a.SubjectKey=d.USUBJID; quit;data collected; set joined; length DOMAIN $2 STUDYID USUBJID LBORRES DAYDATE REFDAY $1024; DOMAIN='LB'; STUDYID=StudyOID; USUBJID=SubjectKey; LBSEQ=input(ItemGroupRepeatKey,best32.); LBORRES=Value;if missing(Value) then LBSTAT='NOT DONE'; if LBSTAT='NOT DONE' then LBORRES=''; DAYDATE=''; REFDAY=''; if lengthn(LBDTC)>=10 then DAYDATE=substr(LBDTC,1,10); if lengthn(RFSTDTC)>=10 then REFDAY=substr(RFSTDTC,1,10); run;data eligible; set collected; if not missing(LBORRES) and not missing(DAYDATE) and (missing(REFDAY) or DAYDATE<=REFDAY); run;proc sort data=eligible; by STUDYID USUBJID LBTESTCD LBSPEC descending DAYDATE descending LBSEQ; run;data flagged; set eligible; by STUDYID USUBJID LBTESTCD LBSPEC; if first.LBSPEC; length LBLOBXFL $1; LBLOBXFL='Y'; run;proc sql; create table result as select a.*,b.LBLOBXFL from collected a left join flagged b on a.STUDYID=b.STUDYID and a.USUBJID=b.USUBJID and a.LBSEQ=b.LBSEQ and a.LBTESTCD=b.LBTESTCD and a.LBSPEC=b.LBSPEC; quit;proc sql;  create table final as select DOMAIN, STUDYID, USUBJID, LBSEQ, LBTESTCD, LBSPEC, LBORRES, LBDTC, LBSTAT, LBLOBXFL from result;quit;proc export data=final outfile="/app/output/lb.csv" dbms=csv replace; run;