Review Question
The research question for this review is: What is the published data on the predictive value of the GMA for the diagnosis of CP by two years of age in neonates born at term or late-preterm with a diagnosis of NE?
Study Design
A scoping method is chosen for this type of review as to fulfilling of the objective of the review it requires searching and assessing a wide range of research methodologies involving the use of the GMA in CP prediction. A scoping review will capture all types of relevant research on the topic in a systematic, transparent, rigorous and reproducible manner. This scoping review will be conducted in accordance with the JBI methodology for scoping reviews26. The objectives, inclusion criteria and methods for this scoping review are detailed in advance and documented in a proposal (included as Additional file 1). The title of our review was registered with JBI.
Inherent in the nature of the scoping review is the inclusiveness of a wide range of literature, and so we anticipate differences in the data quality. Critical appraisal and data synthesis therefore will be challenging in terms of conclusive evidence as opposed to in a systematic review. The scoping review methodology is however especially advantageous to our question as these types of reviews target areas that have not been comprehensively assessed before.
Eligibility Criteria
The participant, concept, context (PCC) framework for scoping reviews will be used to define the review focus and can be found in Table 2.
Table 2 Inclusion and exclusion criteria for the prediction of CP by the GMA in late-preterm and term neonates with NE |
| Inclusion criteria | Exclusion criteria |
Participants | Neonates ≥ 34 + 0 weeks GA Diagnosis of NE GMA done between birth up to six months of life Assessment for CP by at least two years of age | Neonates < 34 + 0 weeks GA No diagnosis of NE No GMA done between birth up to six months of age or with only automated application of GM No assessment of CP by two years of age Neonates born with: - life threatening congenital abnormalities - congenital viral infections - an abnormal karyotype and - metabolic disorders |
Concept | GMA as a predictor of CP by two years of age is the main concept. | |
Context | Studies that reported on: - Newborns with NE managed in hospitals and diagnosed by the standard of care (neurological history and examination) - Studies from all countries that have outcomes reported in the acute neonatal and in the follow-up period by two years of age - Studies in the English language only | |
Note. CP = cerebral palsy, GA = gestational age, GMA = general movements assessment, NE = neonatal encephalopathy |
Participants
This review will consider studies that include neonates ≥ 34 + 0 weeks GA diagnosed with NE with a GMA done between birth to six months of life and an assessment for CP by at least two years of age (Table 2, Appendix II).
Reviews with neonates born at < 34 weeks GA, those without a diagnosis of NE and those born with life threatening congenital abnormalities, congenital viral infections, an abnormal karyotype and metabolic disorders will be excluded. Those studies without a GMA or with any automated application of the GMA will also be excluded.
Concept
GMA as a predictor of CP by two years of age is the main concept. Studies that report on sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) will be considered for inclusion. Detailed definition of concepts can be found in Table 3.
Context
This review will consider studies that reported on newborns with an existing diagnosis of NE managed in hospitals and diagnosed by the standard of care assessment of a neurological history and examination. Studies will be considered from all countries that have outcomes reported in the acute neonatal and in the follow-up period by two years of age. Studies in the English language only will be considered as there is no team member with adequate language skills to translate from any other language.
Table 3 Definitions of concepts |
Concepts | Definition |
Neonatal encephalopathy | A clinically defined syndrome of disturbed neurologic function in the earliest days of life in an infant born at or beyond 35 weeks of gestation, manifested by a subnormal level of consciousness or seizures, and often accompanied by difficulty with initiating and maintaining respiration and depression of tone and reflexes3 |
Late-preterm | Neonates ≥ 34 + 0 to 36 + 6 weeks GA27 |
Term | Neonates 37 + 0 to 42 + 6 weeks GA27 |
Cerebral palsy | A group of permanent disorders of the development of movement and posture causing activity limitations that are attributed to non-progressive disturbances that occurred in the developing fetal or infant brain28 |
General movements | These are spontaneous movements present from early fetal life until about six months of life. GMs are variable, complex movements that occur frequently, lasting long enough to be observed. The whole body is involved in a variable sequence of limbs, neck, and trunk movements. Waxing and waning in intensity, force and speed, they have a gradual beginning and end. They involve rotations along the limb axis. Slight changes in direction are responsible for their fluid elegance. Impairment of the nervous system cause the loss of GMs complexity and variability resulting in monotonous and poor-quality movements. Specific abnormal GM patterns have been identified that reliably predict later cerebral palsy: 1) Cramped-synchronized GMs – a persistence of rigid movements that lack the normal fluidity. Contractions and relaxations occur almost concurrently in limb and trunk muscles. 2) The absence of fidgety GMs - fidgety movements are small movements of moderate speed with variable acceleration of neck, trunk, and limbs in all directions. Normally, they are the predominant movement pattern in an awake infant at 3 to 5 months29 (Einspieler 2005) |
General movements assessment | A comfortably dressed infant, preferably with bare arms and legs, is videoed in supine position. The duration of the video recording will depend on the age of the infant with premature infants requiring up to 30 to 60 minutes. Term age and older require 5 to 10 minutes of optimal recording. This recording does not require the observer’s presence. The trained observer reviews the recording later. The assessment is based on global visual Gestalt perception without acoustic signal to reduce distraction. Two to three recordings of the preterm, one recording at term or early post-term age or both, and at least one recording between 9- and 15-weeks’ post-term forms the basis of a developmental trajectory. An individual developmental trajectory indicates the consistency or inconsistency of normal or abnormal findings29 |
Sensitivity | The proportion of true positives that are correctly identified in a sample, or the true positive rate30 |
Specificity | The proportion of true negatives that are correctly identified in a sample, or the true negative rate30 |
Positive predictive value | The proportion of patients with positive test results who are correctly diagnosed31 |
Negative predictive value | The proportion of patients with negative test results who are correctly diagnosed31 |
Note. GA = gestational age, GMs = general movements |
Search strategy
A search strategy will be developed, with the support from a specialist in systematic reviews, to identify the published literature. A range of electronic databases will be searched to include medicine, nursing, allied health professions, sociology, psychology, education and social work. This scoping review will consider both experimental and quasi-experimental study designs including randomized controlled trials, non-randomized controlled trials, before and after studies and interrupted time-series studies. In addition, systematic reviews that meet the inclusion criteria will be considered. Text and opinion papers will not be considered for inclusion in this scoping review as this is a highly specific and medical topic. Studies published from at least 1970 will be included as this is around the time when the GMA was first introduced in neonatology as a potential predictor of neuromotor outcomes12. The reference lists of articles will be scanned and experts in the infant developmental field will be consulted to identify studies relevant to our topic.
The search strategy will be phased, firstly created in Ovid Medline using a combination of index terms and keywords around general movements, Prechtl, brain disease, HIE and perinatal asphyxia. An initial limited search of Ovid Medline, Embase and PsychINFO was undertaken to identify articles on the topic (See Additional file 2). There were no previous similar reviews. The text words contained in the titles and abstracts of relevant articles, and the index terms used to describe the articles from this limited search will then be used to develop a more refined full search strategy in the second phase, for MEDLINE, Embase, PsychINFO, Scopus and CINAHL (Appendix III). The search strategy, including all identified keywords and index terms, will be adapted for each included information source.
Study selection
EndNote X9 will be used for citation collation. Duplicates will be removed manually. Covidence will be used for screening by two independent reviewers (JS and ML). Disagreements will be resolved through a third reviewer (RB). The results of the search will be reported in a Preferred Reporting Items for Systematic Reviews and Meta-analyses extension for scoping reviews (PRISMA-ScR) flow diagram32.
Data extraction, analysis and synthesis
Each article will be assessed independently by two authors (JS and RB). Extraction will be done using a data extraction tool developed by the reviewers. Excluded studies closely meeting the inclusion criteria will be included in a separate table as they may contain many elements of our inclusion criteria but not present separately the specific criteria of our interest. Further investigation of their data may provide significant results. Authors will be contacted to access further information and reassess eligibility of these studies.
The data extracted from the identified studies will include specific details about the population, concept and context. Two tables will be generated with the first table having information on the key characteristics of each study, including author, year of publication, geographical setting, type of study, demographics of the participants, period over which the study was conducted, the method of identification of neonates at high-risk, if therapeutic hypothermia was instituted as management for NE, type of spontaneous movement assessment used, age at which participants were assessed, the age at which CP was diagnosed and the methods used for neurological examination in the studies. The second table will have information on the key findings, the predictive indices used for the GMA in relation to CP (sensitivity, specificity, PPV and NPV), limitations of the studies and where relevant, reasons for exclusion in the studies that met most but not all of the inclusion criteria. These lists will be iterative. As the process evolves, the data extraction form may require modification to ensure all relevant information is included. Additionally, even though this was a scoping review and does not require a critical appraisal, the critical appraisal tool for JBI33 will helped to identify differences and similarities between the included studies. The answers to the JBI critical appraisal tool will be detailed in a table.