Early vs Late First Feed Analysis

Executive Summary

Sample Distribution: 332 subjects with first feeding <35 weeks PMA vs 124 subjects ≥35 weeks PMA 35-week Threshold Pattern: 72.8% of subjects had first oral feeding before 35 weeks PMA Statistical Finding: No significant difference in time to full oral feeding between groups (p=0.6379) Medical Variables: Statistically associated with timing groups: o2_device_at_36_weeks, birth_weight_grams, mechanical_ventilation, gestational_age_weeks Interaction Effects: No significant interaction effects detected

Cross-tabulation Analysis

Analysis of sample distribution across feeding timing and medical strata:

Sample Size by Group: | | DID require respiratory support at 36 weeks | did NOT require respiratory support at 36 weeks | All | |:----------------------------------------------------|----------------------------------------------:|--------------------------------------------------:|------:| | ('Late feeder (≥35w)', 'Moderate preterm (≥28w)') | 8 | 25 | 33 | | ('Late feeder (≥35w)', 'Extremely preterm (<28w)') | 19 | 10 | 29 | | ('Early feeder (<35w)', 'Moderate preterm (≥28w)') | 15 | 106 | 121 | | ('Early feeder (<35w)', 'Extremely preterm (<28w)') | 18 | 27 | 45 | | ('All', '') | 60 | 168 | 228 |

Statistical Test: Chi-square test of independence between early feeding and oxygen support: - χ² = 11.849 - p-value = 0.0006 - Cramér's V = 0.228

Group Comparisons

Overall Comparison: Early vs Late Feeders - Early feeders (n=166): 15.6 ± 12.5 days - Late feeders (n=62): 16.5 ± 14.9 days - t-test: t = -0.471, p = 0.6379, Cohen's d = -0.070

Stratified Comparisons: Moderate preterm (≥28w): - Early: 13.0 ± 11.2 days (n=121) - Late: 13.5 ± 15.5 days (n=33) - p = 0.8313, Cohen's d = -0.042

Extremely preterm (<28w): - Early: 22.6 ± 13.2 days (n=45) - Late: 20.0 ± 13.6 days (n=29) - p = 0.4092, Cohen's d = 0.198

Medical Factors Analysis

Analysis of medical factors associated with early vs late feeding decisions: o2_device_at_36_weeks: - χ² = 11.849 - p-value = 0.0006 - Cramér's V = 0.228

c_section: - χ² = 0.234 - p-value = 0.6283 - Cramér's V = 0.036

birth_weight_grams: - Early feeders: 1287.4 ± 407.3 - Late feeders: 1058.5 ± 382.8 - t-test: p = 0.0002, Cohen's d = 0.571

mechanical_ventilation: - χ² = 15.607 - p-value = < 0.0001 - Cramér's V = 0.262

medicalcomplexity: - χ² = 5.563 - p-value = 0.0619 - Cramér's V = 0.156

gestational_age_weeks: - χ² = 17.814 - p-value = 0.0227 - Cramér's V = 0.280

Interaction Analysis

Testing for interaction effects between feeding timing and medical strata: early_feeder_x_extremely_preterm: Error - 'str' object has no attribute 'get' early_feeder_x_o2_device_at_36_weeks: Error - 'str' object has no attribute 'get' early_feeder_x_medicalcomplexity: Error - 'str' object has no attribute 'get'

Time-based Relationships

Analysis of time-based relationships to avoid PMA multicollinearity: Overall: - Correlation (time_to_first vs time_to_FOF): 0.221 - Sample size: 228 - Time to first feeding: 40.9 ± 20.5 days - Time to full feeding: 15.9 ± 13.1 days

Late Feeders: - Correlation (time_to_first vs time_to_FOF): 0.203 - Sample size: 62 - Time to first feeding: 59.1 ± 21.2 days - Time to full feeding: 16.5 ± 14.9 days

Early Feeders: - Correlation (time_to_first vs time_to_FOF): 0.266 - Sample size: 166 - Time to first feeding: 34.2 ± 15.6 days - Time to full feeding: 15.6 ± 12.5 days