🚨 Respiratory Stratified Analysis
Dataset Summary¶
| Group | N | Percentage |
|---|---|---|
| With O2 Support | 60 | 26.3% |
| Without O2 Support | 168 | 73.7% |
| Total | 228 | 100.0% |
Analysis Variables¶
Outcome: time_to_fof
Predictor: time_to_first
Stratification: o2_device_at_36_weeks
Confounders: gestational_age_weeks, birth_weight_grams, medicalcomplexity
Interaction Analysis¶
Respiratory Support Interaction Testing
Tests whether feeding relationships differ by respiratory support status.
Unadjusted model: - Interaction coefficient: -0.094 - Interaction p-value: 0.3523 - Model R²: 0.070
Adjusted model (including confounders): - Interaction coefficient: -0.083 - Interaction p-value: 0.4074 - Model R²: 0.114
Model diagnostics warning: High multicollinearity detected. Residuals may not be normally distributed.
Statistical conclusion: No significant interaction (p = 0.4074)
With O2 Support Group Analysis¶
Sample size: 60 infants
Analysis includes: Optimal timing identification and slope comparison
With O2 Support: Optimization Analysis¶
Unadjusted quadratic model: - Sample size: 60 - R²: 0.045 - Linear coefficient: 0.595 (p = 0.1057) - Quadratic coefficient: -0.005 (p = 0.1164)
No optimal found in data range (unadjusted)
With O2 Support: Adjusted Model¶
Adjusted quadratic model: - Sample size: 60 - Adjusted R²: 0.056 - Adjusted quadratic coefficient: -0.002 (p = 0.5351)
No optimal found in data range (adjusted)
With O2 Support: Slope Comparison¶
Slope comparison using median (no optimal found) (57.6 days):
Interaction p-value: 0.1564
With O2 Support: Slope Results¶
| Group | N | Slope | SE | p-value |
|---|---|---|---|---|
| < 57.6 days | 30 | 0.13459 | 0.183585 | 0.469579 |
| ≥ 57.6 days | 30 | -0.253575 | 0.197144 | 0.208893 |
Without O2 Support Group Analysis¶
Sample size: 168 infants
Analysis includes: Optimal timing identification and slope comparison
Without O2 Support: Optimization Analysis¶
Unadjusted quadratic model: - Sample size: 168 - R²: 0.042 - Linear coefficient: -0.104 (p = 0.5696) - Quadratic coefficient: 0.003 (p = 0.1861)
Unadjusted optimal: 20.7 days
Without O2 Support: Adjusted Model¶
Adjusted quadratic model: - Sample size: 168 - Adjusted R²: 0.053 - Adjusted quadratic coefficient: 0.004 (p = 0.0633)
Adjusted optimal: 56.9 days
Without O2 Support: Optimization Plot¶
Quadratic model fit with optimal point marked.
Without O2 Support: Slope Comparison¶
Slope comparison using adjusted optimal point (56.9 days):
Interaction p-value: 0.9708
Without O2 Support: Slope Results¶
| Group | N | Slope | SE | p-value |
|---|---|---|---|---|
| < 56.9 days | 150 | 0.0979199 | 0.0825746 | 0.237588 |
| ≥ 56.9 days | 18 | 0.090033 | 0.217715 | 0.684703 |
Summary: Answers to PI's Key Questions¶
Question 1: Do infants with O2 support have different feeding relationships? NO - No significant interaction
Question 2: Do they show different statistical patterns? YES - One group has optimal timing, the other does not
Question 3: Is optimal timing different between groups? YES - With O2: No optimal found, Without O2: 56.9 days