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Top Diagnoses in Pediatric Outpatient
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Top Diagnoses in Pediatric Outpatient

MediumSQL · PostgreSQL

Problem

Walk me through the SQL logic you would use to identify the top three most frequent diagnoses in our pediatric outpatient clinic at Children’s Hospital of Philadelphia over the last year.

Use completed pediatric outpatient encounters and define frequency as the number of distinct encounters associated with each diagnosis. Exclude encounters outside the rolling one-year period.

Output

  1. One row per selected diagnosis with diagnosis_name and encounter_count
  2. Return exactly three diagnoses, ordered by encounter count descending, then diagnosis name ascending to break ties

Schema

encounters
ColumnTypeDescription
encounter_idPKINTUnique outpatient or inpatient encounter identifier
encounter_dateDATEDate on which the encounter occurred
clinic_typeVARCHAR(100)Clinical setting for the encounter
encounter_statusVARCHAR(30)Encounter completion status
encounter_diagnoses
ColumnTypeDescription
encounter_diagnosis_idPKINTUnique diagnosis assignment identifier
encounter_idINTEncounter associated with the diagnosis
diagnosis_idINTDiagnosis associated with the encounter
diagnoses
ColumnTypeDescription
diagnosis_idPKINTUnique diagnosis identifier
diagnosis_nameVARCHAR(150)Clinical diagnosis name
diagnosis_groupVARCHAR(100)Broad clinical grouping
Tablesencountersencounter_diagnosesdiagnoses
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Your question is Top Diagnoses in Pediatric Outpatient. Start with the requirements and the three tables in the Question tab.

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