Santamaria 2014.

Methods	3‐arm parallel group RCT followed up for 2 years (but data currently only available up to 1 year follow‐up). Unit of randomisation: patient
Participants	Setting: Germany (2 other countries, Lithuania and the UK, are involved in this study but no data were available for them yet). All children attended secondary care Sample size: 169 randomised from 181 eligible, all analysed Number screened: not stated in manuscript, researcher contacted and number unknown Number eligible: 181 Number randomised: 169 Number analysed: 148 Age: 3‐8 years old Sex: 96 boys and 73 girls Teeth/lesions: primary molars; maxillary first = 62; maxillary second = 29; mandibular first = 54; mandibular second = 24. ICDAS; code 3 = 6 teeth, 4 = 25 teeth, 5 = 138 teeth Inclusion criteria for participants: 3 to 8 years no systemic disease requiring special considerations during dental treatment Inclusion criteria for teeth: primary molar tooth with caries into dentine involving at least 2 dental surfaces (diagnosed according to ICDAS codes 3–5 no clinical or radiographic signs or symptoms of pulpal or periradicular pathology (including pain) Where more than 1 tooth per child was eligible for inclusion, the next tooth on the prescribed treatment plan, at the time of screening by one of the researchers (RS), was chosen for the study
Interventions	Group 1 (n = 52): SSC, using the Hall Technique Group 2 (n = 65): fillings using resin composite Group 3 (n = 52): non‐restorative caries treatment
Outcomes	Major failure Minor failure Pain, rated by child with 5‐point VASOF scale Behaviour ‐ Frankl Behaviour rating scale by dentist Parent rating of child's behaviour Parent rating of child's comfort Parent rating of satisfaction Dentist rating of patient's discomfort, ease of treatment and relative time taken for procedure Gingival bleeding
Source of Funding	The study was supported by the Paediatric Dentistry Department of Greifswald University, Germany
Declaration of interest	No conflict of interest declared
Notes	NCT01797458 Study completion expected in December 2014. These are only the preliminary results for outcomes assessed immediately after treatment completion, and at up to 1 year of follow‐up in 1 of the 3 countries (Lithuania, Germany, Scotland (UK)) participating in the study
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "Following consent, participants were sequentially randomised, using a computer‐generated random number list with allocation concealment, to one of three arms." Comment: The randomisations were done independently by each country participating in the study
Allocation concealment (selection bias)	Low risk	Comment: Randomisation only performed after participant consented to participation (based on preference paper and communication from authors.)
Blinding of participants and personnel (performance bias) All outcomes	High risk	Comment: No blinding, participant and operator aware of different treatments as restorations look different. Unclear whether this would affect level or quality of care
Blinding of outcome assessment (detection bias) All outcomes	High risk	Comment: Unclear whether participants were blinded when questions related to intraoperative pain were asked immediately after procedure. Outcome assessors (dentists) could not be blinded
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Data for the full trial are currently incomplete and were not available for 2 of the 3 countries involved in the study. Only the data from Germany are currently available. 148/169 (87.5%) participants randomised available for analysis at 1 year. Proportion of exclusions balanced across treatment arms (15.3% for Hall Technique, 15.3% for filling, 14.8% for non restorative caries). Study stated that "characteristics of participants who left during the study were comparable to those who remained in the study." Main reasons for dropout were in general: failure to return 67% (n = 14) or participants moved to another city/country 33% (n = 7) (information obtained from study authors)
Selective reporting (reporting bias)	Low risk	All outcomes regarding pain or discomfort were measured immediately after the procedure as stated in the protocol Only the 1‐year data were available for the 2014 review. The study is still ongoing; this paper reported only the German study population
Other bias	Low risk	No other potential biases detected

Abbreviations

d3: decayed at the d3 level
 dmft: number of decayed, missing and filled primary teeth
 ft: number of filled primary teeth
 GDP: general dental practitioner
 ICDAS: International Caries Detection and Assessment System
 mt: number of missing primary teeth
 MTA: mineral trioxide aggregate
 MTA/SSC: mineral trioxide aggregate/ stainless steel crown
 NHS: National Heatlh Service
 PMC: preformed metal crown
 RCT: randomised controlled trial
 RMGIC/CRRs: resin modified glass ionomer cement/ composite resin restorations
 SD: standard deviation
 SSC: stainless steel crown
 USPHS: United States Public Health Service
 VASOF: visual analogue scale of faces