The only eligible r and omised clinical trial did not demonstrate any consistent effects of NIRS plus a guideline on the assessed clinical outcomes .
The trial was , however , only powered to detect difference in cerebral oxygenation , not morbidities or mortality .
BACKGROUND Cerebral injury and long-term neurodevelopmental impairment is common in extremely preterm infants .
Cerebral near-infrared spectroscopy ( NIRS ) enables continuous estimation of cerebral oxygenation .
This diagnostic method coupled with appropriate interventions if NIRS is out of normal range ( that is cerebral oxygenation within the 55 % to 85 % range ) may offer benefits without causing more harms .
Therefore , NIRS coupled with appropriate responses to abnormal findings on NIRS needs assessment in a systematic review of r and omised clinical trials and quasi-r and omised studies .
OBJECTIVES To evaluate the benefits and harms of interventions that attempt to alter cerebral oxygenation guided by cerebral NIRS monitoring in order to prevent cerebral injury , improve neurological outcome , and increase survival in preterm infants born more than 8 weeks preterm .
Contradicted and initially stronger effects in highly cited clinical research.
CONTEXT Controversy and uncertainty ensue when the results of clinical research on the effectiveness of interventions are subsequently contradicted . Controversies are most prominent when high-impact research is involved . OBJECTIVES To underst and how frequently highly cited studies are contradicted or find effects that are stronger than in other similar studies and to discern whether specific characteristics are associated with such refutation over time . DESIGN All original clinical research studies published in 3 major general clinical journals or high-impact-factor specialty journals in 1990 - 2003 and cited more than 1000 times in the literature were examined . MAIN OUTCOME MEASURE The results of highly cited articles were compared against subsequent studies of comparable or larger sample size and similar or better controlled design s. The same analysis was also performed comparatively for matched studies that were not so highly cited . RESULTS Of 49 highly cited original clinical research studies , 45 cl aim ed that the intervention was effective .  Of these , 7 ( 16 % ) were contradicted by subsequent studies , 7 others ( 16 % ) had found effects that were stronger than those of subsequent studies , 20 ( 44 % ) were replicated , and 11 ( 24 % ) remained largely unchallenged . Five of 6 highly-cited nonr and omized studies had been contradicted or had found stronger effects vs 9 of 39 r and omized controlled trials ( P = .008 ) . Among r and omized trials , studies with contradicted or stronger effects were smaller ( P = .009 ) than replicated or unchallenged studies although there was no statistically significant difference in their early or overall citation impact . Matched control studies did not have a significantly different share of refuted results than highly cited studies , but they included more studies with " negative " results . CONCLUSIONS Contradiction and initially stronger effects are not unusual in highly cited research of clinical interventions and their outcomes . The extent to which high citations may provoke contradictions and vice versa needs more study . Controversies are most common with highly cited nonr and omized studies , but even the most highly cited r and omized trials may be challenged and refuted over time , especially small ones
The only eligible r and omised clinical trial did not demonstrate any consistent effects of NIRS plus a guideline on the assessed clinical outcomes .
The trial was , however , only powered to detect difference in cerebral oxygenation , not morbidities or mortality .
BACKGROUND Cerebral injury and long-term neurodevelopmental impairment is common in extremely preterm infants .
Cerebral near-infrared spectroscopy ( NIRS ) enables continuous estimation of cerebral oxygenation .
This diagnostic method coupled with appropriate interventions if NIRS is out of normal range ( that is cerebral oxygenation within the 55 % to 85 % range ) may offer benefits without causing more harms .
Therefore , NIRS coupled with appropriate responses to abnormal findings on NIRS needs assessment in a systematic review of r and omised clinical trials and quasi-r and omised studies .
OBJECTIVES To evaluate the benefits and harms of interventions that attempt to alter cerebral oxygenation guided by cerebral NIRS monitoring in order to prevent cerebral injury , improve neurological outcome , and increase survival in preterm infants born more than 8 weeks preterm .