Identifying Problem Sources at Data Entry and Collection

National Center for Immunization & Respiratory Diseases

Influenza Division

Nishan Ahmed

Regional Training Workshop on Influenza Data Management

Phnom Penh, Cambodia

July 27 – August 2, 2013

Methods to Identify Data Problems

• Data collection Review of paper form for completeness Review of key fields for validation Sign off by data collector and reviewer

• Data entry Double Data Entry Built in checks at the data entry level

Field Validation Rules Keeping data consistent across the record

Data Collection• Review of paper form - onsite

Data collected on form Form is reviewed by second person for completeness Form sent to central location for entry into data management

system

• Review of key indicators – onsite Data collected on form Form reviewed by second person for accuracy and

completeness of key indicators Date of birth vs. date of admission Gender vs. pregnancy Temperature falls in pre-determined acceptable range

• Sign off by data collector and reviewer

Data Entry

• Double Data Entry Pros

All data is entered twice for ease of comparison ACCESS - Programmed computer-run check for

inconsistencies between the two entries Useful in picking out keystroke mistakes

Cons EXCEL – requires several steps to review and

validate Not useful when dealing with systematic errors or

incorrect measurements Time consuming procedure - costly

Data Entry

Data Entry

Data Entry

Data Entry

Data Entry

Data Entry

Data Entry• Built-in checks may include:

Field Validation Rules Date Validations

Date of onset should be on or before the date of specimen collection, date of consultation or admission

Date of sample collection should be before date received at laboratory

Other validity checks Temperature should be a valid measured temperature

(i.e. between 35ºC and 41ºC) Pregnancy status should only be “yes” if patient is female

and of child bearing age Test results should be consistent with the type of test

performed (i.e. a rapid test will not yield Influenza A subtyping results)

Data Entry

• Built-in checks may include: Forced consistency

across fields Forced –

Data entry screen will not let you proceed with incorrect data,

Voluntary - Gives a warning that

the value entered may be wrong but will let you continue

Data EntrySetting Up Field Validation Rules On Tables - ACCESS

Data EntryMacros to Ensure Data Consistency Across Fields on Forms - ACCESS

Data Entry

Macros to Ensure Data Consistency Across Fields on Forms - ACCESS

Data EntryMacros to Ensure Data Consistency Across Fields on Forms - ACCESS

Data Entry

• Built-in checks may include: System queries at site to aid in fixing data

errors immediately Contain additional data validation criteria

Additional validations that might be important For example:

Might check for dates that seem reasonable for the time period, or pull a query for dates that are too far apart (i.e. date of onset is more than a week from the date of consultation)

Data EntrySetting up System Queries - ACCESS

Data EntrySetting up System Queries - ACCESS

Final Thoughts• There are many different ways to ensure data

quality at the data entry and data collection level Double Data Entry

Good for finding mis-keyed values Built-in checks at data entry

Can include both single field validations and controls to keep data consistent across fields

System queries For systematic data checks and potential error

identification

• Use what works for you and your data process

Exercise

• Objective: Create data validation controls/data checks for

your system1) Create built-in data checks in your database (i.e.

date validations)

2) Create system queries so that sites can assist in the data cleaning process

For more information please contact Centers for Disease Control and Prevention1600 Clifton Road NE, Atlanta, GA 30333Telephone, 1-800-CDC-INFO (232-4636)/TTY: 1-888-232-6348E-mail: cdcinfo@cdc.gov Web: www.cdc.gov

The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention.

THANK YOU!!!

National Center for Immunization & Respiratory Diseases

Influenza Division