**5. Conclusions**

Given the above limitations of our study, particularly its small sample size, the comparatively small di fferences observed between the three di fferent modes of nasal respiratory support investigated should not prevent clinicians from preferring s-NIPPV or vf-NCPAP over cf-NCPAP when trying to prevent or treat IH episodes in very preterm infants.

**Supplementary Materials:** The following are available online at http://www.mdpi.com/2227-9067/7/10/168/s1, Figure S1: Study protocol CPAP study, Figure S2: CONSORT flow chart, Table S1: CONSORT checklist.

**Author Contributions:** Conceptualization and methodology, A.P., R.S., M.S.U. and C.F.P.; investigation, M.G., R.S., K.B., B.H.; formal analysis M.G., M.S.U., C.F.P.; data curation M.G., R.S.; writing—original draft preparation, M.G., M.S.U., C.F.P.; writing—review & editing, M.G., C.F.P.; visualization, M.G., C.F.P.; supervision C.F.P. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding. **Acknowledgments:** The authors thank Magnus von Lukowicz for helping with patient recruitment and acknowledge support by Open Access Publishing Fund of University of Tuebingen.

**Conflicts of Interest:** The authors declare no conflict of interest.
