Table 2 Quality assessment tool for birth prevalence estimates

Case definition^a

The case definition is complete (including both screening positive and confirmed cases)

The case definition is partially complete (lacks either the definition of screening positive or of confirmed cases)

The case definition is incomplete for both screening positive and confirmed cases

Study setting/source population

Mandatory population-wide newborn screening program

General population from a well-defined region and time

Catchment area of a hospital or other medical facility

Hospital or laboratory records or disease registry

Surveys (e.g., to health care providers)

Personal communication

Unclear or not reported

Statistical methods

The denominator is the number of newborns screened, and cases in the numerator arise from the population in the denominator

If any quantity is estimated rather than directly measured, estimations are in line with the criteria described here

The denominator is the overall number of births rather than the number screened

Cases in the numerator do not arise from the population in the denominator

Unclear or not reported

Precision of prevalence estimate^b

Half the width of the 95% confidence interval is less than half of the prevalence

Half the width of the 95% confidence interval is between half of the prevalence and the prevalence^c

Half the width of the 95% confidence interval is greater than the prevalence

Confidence interval is not estimable

Diagnostic method used for case confirmation^d

Tandem mass spectrometry, high-performance liquid chromatography, column chromatography, (rapid) ion exchange chromatography, quantitative amino acid analyzer, positive mutational analysis, or enzymatic assay (including colorimetric, fluorimetric, and ELISA)

Guthrie test, bacterial inhibition assay, thin layer or paper chromatography

Other methods, or those where urine is used as the assay substrate

Unclear or not reported