asthma_predictive_index: Asthma Predictive Index (API)

In cliot: Clinical Indices and Outcomes Tools

Asthma Predictive Index (API)

Description

Calculates the Stringent Asthma Predictive Index (API) to predict the likelihood of developing active asthma at school age in children younger than 3 years who present with frequent wheezing. This tool is based on the original Castro-Rodriguez criteria derived from the Tucson Children's Respiratory Study.

Usage

asthma_predictive_index(wheezing_freq_ge_4, parent_asthma, eczema,
                        allergic_rhinitis, wheezing_apart_colds,
                        eosinophilia_ge_4)

Arguments

wheezing_freq_ge_4	Numeric (0 or 1). Does the child have a history of frequent wheezing (>= 4 episodes/year) with at least one physician-confirmed episode? (Entry Criterion).
parent_asthma	Numeric (0 or 1). Parental history of asthma. (Major Criterion).
eczema	Numeric (0 or 1). Physician-diagnosed atopic dermatitis (eczema). (Major Criterion).
allergic_rhinitis	Numeric (0 or 1). Physician-diagnosed allergic rhinitis. (Minor Criterion).
wheezing_apart_colds	Numeric (0 or 1). Wheezing apart from colds. (Minor Criterion).
eosinophilia_ge_4	Numeric (0 or 1). Peripheral eosinophilia >= 4%. (Minor Criterion).

Value

A list containing:

Result	"Positive Stringent API" or "Negative Stringent API".
Interpretation	Prognostic information regarding the risk of asthma at ages 6-13.
Stats	Predictive values (PPV, Specificity) derived from the validation studies.

References

Castro-Rodriguez JA, Holberg CJ, Wright AL, Martinez FD. A clinical index to define risk of asthma in young children with recurrent wheeze. Am J Respir Crit Care Med. 2000;162(4 Pt 1):1403-1406. doi:10.1164/ajrccm.162.4.9912111

Examples

# Example 1: Positive API
# Freq wheezing, Parent Asthma (Major), No others
# Result: Positive (1 Major met)
asthma_predictive_index(1, 1, 0, 0, 0, 0)

# Example 2: Positive API via Minor Criteria
# Freq wheezing, No Major, Allergic Rhinitis + Eosinophilia (2 Minor)
asthma_predictive_index(1, 0, 0, 1, 0, 1)

# Example 3: Negative API
# Freq wheezing, only Eosinophilia (1 Minor)
asthma_predictive_index(1, 0, 0, 0, 0, 1)

cliot documentation built on Dec. 1, 2025, 1:06 a.m.