Table 1.

Canadian Primary Care Sentinel Surveillance Network Data Quality Issues Identified During Phase 1 and Our Initial Remediation Strategy

Data Quality Issue	Description	Remediation Strategy
“Dirty data”	Misspelled words, extra words in field, inconsistent strings (“ex smoker,” “ex-smoker”), multiple diagnoses in a single field	Cleaned by data managers using synonym dictionaries and cleaning algorithms
Identifiable Data	Names, phone numbers, and other identifying information in diagnosis or reason for visit fields	Clean using a de-identification engine
Missing data	Dosages, dates of onset, occupation, ethnicity	Ask and train physicians and/or staff to enter appropriate data
Inconsistent data	Diagnoses stored in several different places—notes, PMH, problem list, Inconsistent Risk Factors coexisting—smoker, ex-smoker	Use physician as “gold standard” for confirming diagnoses; use dates to determine latest status of risk factor
Lacking Metadata	Referral to “Dr. Jones,” but Dr. Jones’ speciality is not listed	Work with EMR vendors to include specialty in address database; encourage staff to enter specialty into address databases
Inappropriate Metadata	Diagnosis not in problem list, medication in encounter notes	Ask physicians to enter “gold standard” diagnosis into Problem List for all patients with an index disease
Insufficient Meta Data	In 2 EMRs, Problem List, Risk Factors and Procedures appear in the same table with no metadata to distinguish the 3 types of data	Work with EMR vendors to separate the 3 different types of data
Lacking standardization	Multiple, changing, inconsistent names or results for lab tests, eg, HbA1C, glycosylated hemoglobin, hemoglobin A1C; 7% vs 0.07 for test results	Work with National standards bodies to encourage uptake of standards
Lacking data feeds	Lab results not coming in electronically	Encourage local labs to provide laboratory results electronically

PMH, past medical history; EMR, electronic medical record.