From: Screening rules for growth to detect celiac disease: A case-control simulation study
Screening rule | Definition | Parameter | Interpretation | Simulation values |
---|---|---|---|---|
Delta rule*^{^} | For ages e _{1} to 2.5 years, refer if | e _{1} | Age (in years) after which the rule is effective | 0, 0.5, 1 |
(SDS_{2} – SDS_{1}) <g _{1} | g _{1} | Change in SDS | -0.5,-1,-1.5,-2,-2.5,-3 | |
Extended delta rule* | For ages e _{2} to 2.5 years, refer if | e _{2} | Age (in years) after which the rule is effective | 0, 0.5, 1 |
SDS_{2}<f _{1}, AND | f _{1} | SDS cut off level below which the SDS_{2} must lie | -1,-1.3, -1.5,-2, -2.5 | |
(SDS_{2} – SDS_{1}) <g _{2} | g _{2} | Change in SDS | -0.5,-1,-1.5,-2,-2.5,-3 | |
Slowed growth * | For ages e _{3} to 2.5 years, AND | e _{3} | Age (in years) after which the rule is effective | 0, 0.5, 1 |
X_{2} – X_{1} ≥ 3/12 refer if | Minimal three months interval between ages X_{1} and X_{2} | |||
SDS_{2}<f _{2}, AND | f _{2} | SDS cut off level below which the SDS_{2} must lie | -1,-1.3, -1.5,-2, -2.5 | |
(SDS_{2}- SDS_{1})/(X_{2}-X_{1}) < g_{3} | g _{3} | Change in SDS per year | -0.5,-1,-1.5,-2,-2.5 | |
Conditional weight gain rule | For ages e _{4} to 2.5 years, refer if | e _{4} | Age (in years) after which the rule is effective | 0, 0.5, 1 |
weight SDS_{2} <f _{3} AND | f _{3} | SDS cut off level below which SDS_{2} must lie | -1,-1.3, -1.5,-2, -2.5 | |
weight SDSgain = (weight SDS_{2} – r weight SDS_{1})/(√1-r^{2}) <g _{4} | g _{4} | Change in SDS | -0.5,-1,-1.5,-2,-2.5 | |
Absolute SDS rule* | For ages 0 to e _{5} years, refer if | e _{5} | Age (in years) at which the referral level changes | 0, 0.5, 1 |
SDS <f _{4} | f _{4} | SDS cut off level before age e _{5} | -1, -1.3, -1.5, -2, -2.5, -3, -3.5 | |
For ages e _{5} to 2.5 years, refer if SDS <f _{5} | f _{5} | SDS cut off level after age e _{5} | -1, -1.3, -1.5, -2, -2.5, -3 | |
Parental height corrected rule | For ages e _{6} to 2.5 years, refer if | e _{6} | Age (in years) after which the rule is effective | 0, 0.5, 1 |
length SDS <f _{6}, AND | f _{6} | Length SDS must lie below this cut off level | -1, -1.3, -1.5, -2, -2.5 | |
length SDS – TH SDS <g _{5} | g _{5} | Difference between length SDS and target height (TH) SDS | -1, -1.3, -1.5, -2, -2.5 | |
Parental height deflection rule | For ages e _{7} to 2.5 years, refer if | e _{7} | Age (in years) after which the rule is effective | 0, 0.5, 1 |
(length SDS_{2} – length SDS_{1}) <g _{6}, AND | length SDS_{2} – TH SDS | > | length SDS_{1} – TH SDS | | g _{6} | Change in length SDS Length SDS at age X_{1} is closer to it's target height than length SDS at age X_{2} | -0.5,-1,-1.5,-2,-2.5,-3 | |
Combined weight and length deflection rule | For ages e _{8} to 2.5 years, AND | e _{8} | Age (in years) after which the rule is effective | 0, 0.5, 1 |
(weight SDS_{2} – weight SDS_{1}) <g _{7}, AND | g _{7} | Weight change in SDS | -0.25,-0.5,-1,-1.5,-2 | |
(length SDS_{2} – length SDS_{1}) <g _{8}, AND Y_{1} > X_{1} | g _{8} | Length change in SDS Starting point length deflection (Y_{1}) after starting point weight deflection (X_{1}) | -0.25,-0.5,-1,-1.5,-2 |