Table 1.

Study exclusion criteria

Population

Populations with mean or median gestational age greater than 32 weeks

Populations with mean or median postmenstrual age greater than 36 weeks at time of intervention

Populations with a purposeful sample of healthy infants (defined as 3 or more of the following factors: never on oxygen, never on medications, no intraventricular hemorrhage or other perinatal brain injury, or if Apgar scores were >7 at 1 or 5 min)

Interventions

Interventions aimed at reduction of external stimuli (e.g. headphones to reduce noise)

Interventions aimed at reducing pain (e.g. during heel stick or endotracheal suctioning)

Breastfeeding interventions

Therapeutic touch (non-touch, energy-balancing technique)

Pacifier-activated sound (includes use of a learning element)

Vibrating pacifiers (includes use of a learning element)

Breathing bear (no direct intervention to the infant)

NIDCAP (interventions individualized for each infant rather than a uniform, quantifiable intervention)

Non-relevant outcomes

Apnea

Incidence of retinopathy of prematurity

Breastfeeding measures or feeding outcomes

Study design and other factors

Studies published before 1995

Studies with a sample size < 30 without an a priori power calculation or sample size not attained

Observational studies

Pilot or feasibility studies

Studies without a comparison group (case reports or case series)

Systematic reviews that included studies with different EGA and PMA criteria

Primary studies included as part of a relevant systematic review

Non-English language studies

Studies not published in a peer-reviewed journal (conference abstracts or dissertations)

Studies with unclear or incomplete methods, statistical analysis or results

Abbreviations: EGA, estimated gestational age; NIDCAP, Newborn Individualized Developmental Care and Assessment Program; PMA, postmenstrual age.