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Part of Data Quality Maturity Index (DQMI) methodology

Appendix 1: Example of DQMI calculation

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Current chapter – Appendix 1: Example of DQMI calculation


 

Dataset Data item Number of records Valid and complete Defaults Defaults in excess (calculated) Threshold for proportion of defaults (%) Data item score (calculated) Coverage of dataset (calculated)
1 1 2,500 2,400 100 50 2.0 94.0 1.0
1 2 2,500 2,500 100 0 100.0 100.0 1.0
1 3 2,500 2,000 100 100 0.0 76.0 1.0
2 1 1,000 900 900 900 0.0 0.0 1.0
2 2 1,000 800 800 0 100.0 80.0 1.0
2 3 1,000 900 450 450 0.0 45.0 1.0
2 4 1,000 1,000 100 65 3.5 93.5 1.0
3 1 10,000 10,000 - - - 100.0 1.0
3 2 10,000 10,000 - - - 100.0 1.0
4 1 - - - - - - -
5 1 - - - - - - -
7 1 50,000 50,000 100 0 2.0 100.0 1.0
7 2 50,000 49,000 5,000 0 100.0 98.0 1.0
7 3 50,000 45.000 5,000 3,250 3.5 83.5 1.0

Note: '-' denotes that no data was expected


Formulae

\(Defaults\ in\ excess = Total\ Defaults\ - (Threshold\ *\ Number\ of\ Records)\)

\(Data\ Item\ Score = ({Number\ of\ valid\ and\ complete\ records - defaults\ in\ excess\ \over Number\ of\ records}) * 100\)

\(DQMI = \frac{1}{n} \Sigma_{i=1}^n({Number\ of\ valid\ and\ complete\ records - defaults\ in\ excess \over\ Number\ of\ records})_i \ *\ \frac{1}{n}\Sigma^n_{i=1}(C)_i \ *\ 100\)

Where n is the number of data items for which data was submitted, 𝑖 is the index number of each of those data items and C is coverage.

DQMI calculation

\(DQMI = [ ({1 \over 12}) * (0.94 +1.0 +0.76 + 0 +0.8 + 0.45 +0.935 + 1.0 + 1.0 + 1.0 +0.98 + 0.835)] *\)

\( [({1\over 12}) * (1 + 1 + 1 + \frac {1}{3} + \frac {1}{3} + \frac {1}{3} + \frac {1}{3} + \frac {1}{3} + \frac {1}{3} + \frac {2}{3} + \frac {2}{3} + \frac {2}{3})] * 100\)

 

\(DQMI = [( {1 \over 12}) * (9.7)] * [({1 \over 12}) * (7)] * 100 = 47.2\)

 


Last edited: 11 October 2021 5:22 pm