Quality of information and data

Fitness for purpose - data is suitable for doing the job for which it was collected

May not be fit for purpose if:

• Too few items of data
• Not collecting the right data

Evaluating data for accuracy: (Inaccurate if):

• Making data up
• Data is missing
• Mistakes when collecting the data

Evaluating the data for bias: Bias - preference towards a particular result

• Not taking representative sample
• Prompting a certain answer - asking questions in a way that might be prompting person to give a certain answer

Evaluating and questioning accuracy and plausibility of information:

• Is the source reliable?
• Spelling mistakes?
• Reasonable?
• How was the data collected?

Ensuring accuracy/plausibility of information:

• Getting more people to read the work
• Proof read the work
• Use spelling and grammar checkers

Limitations of spelling and grammar checkers:

Spellchecker - program, found with most packages that process text, checks spelling in document and suggests correctly spelt words

Grammar checker - software that checks a doucment for grammatical errors and suggests corrections

Check sentences end with only one full stop, capital letters, common errors

How errors can occur:

• transcription (error made when typing in data using a document as the source of the data
• input
• processing
• transmission
• transposition (error made when characters are swapped around so they are in the wrong order)

Validation is a check performed by a computer program during data entry. Process that ensures that data accepted for processing is sensible and reasonable

Validation checks - checks a developer of a solution sets/creates, using the software in order to restrict the data that a user can enter, so as to reduce errors

DATA TYPE CHECKS - data being entered is the same type as the data type specified for the field

PRESENCE CHECKS - make sure data has been entered into a field

RANGE CHECKS - performed on numbers, number entered within a certain range

LOOK UP LISTS - when enter data, software looks through list of data until it finds a match along with other important data

FORMAT CHECKS - performed on codes to mkae sure they conform to the correct combination of characters

CHECK DIGITS - numbers are placed at the end of the block of numbers and are used to check that the numbers have been entered correctly into the computer

Restricting the user to a list:

• prevents user from entering data that is not on a list
• appropriate when only a small number of checks

Data Verification

Methods:

VISUAL CHECK/ PROOF READING: involves one user carefully reading what they have typed in and comparing it with what is on the data source for any error

DOUBLE ENTRY OF DATA: same data source used to enter the details into ICT system twice and only if the two sets of data are identical will be accepted for processing