Table 2.

LLKardReha-DACH: evidence generation—classification of evidence.

Classification of Scientific Evidence According AWMF Rules	Evaluation of Scientific Evidence
S3	Data acquisition and evaluation: Systematic reviews and meta-analyses were newly performed on the basis of the PRISMA and the MOOSE statements [24,25]. The evaluation of included studies followed the Cochrane risk of bias table (http://tech.cochrane.org/revman/download, currently valid version, accessed on 24 January 2021) for RCTs and the Newcastle–Ottawa Scale (NOS) for controlled cohort studies (CCS) [26]. In addition, a new methodological approach for the evaluation of CCS was developed, applied and published [17]. Reviewing and publication of meta-analyses: Meta-analyses were published in peer-reviewed journals before their results were discussed and graded within the guideline [17,27,28,29]. The guideline text was internally reviewed by the “lead management” followed by external assessment and final judgement by the “steering committee”. Systematic grading of scientific evidence: The scientific evidence acquired by meta-analyses was graded following the Scottish Intercollegiate Guidelines Network (SIGN) grading system (see Supplemental Material) [30]. Consensus-based grading of recommendations: Clinical recommendations were determined in face-to-face sessions of the steering committee according to the definitions outlined in Table 3.
S2k	Data acquisition and evaluation: Scientific evidence was generated on the basis of the most actual and topic-related scientific guidelines, and in addition by a semi-structured evaluation of the scientific literature using PubMed and the Cochrane Library. Review process: All S2k chapters were internally pre-reviewed by the “lead committee” followed by the external and final judgement of the “steering committee” as supervised by the AWMF. Grading of evidence: As content and recommendations of S2k chapters were not based on newly performed meta-analyses, there was no formal grading of the underlying scientific evidence.
Narrative evidence reporting, NER	Data acquisition and evaluation: Scientific evidence was generated on the basis of the most actual and topic-related scientific guidelines. Review process: There was no formal and predefined review process, but all chapters were reviewed by expert members of the “lead management” and “steering committee”. Grading of evidence: There was no newly performed formal grading of the underlying scientific evidence. Scientific evidence as published in current guidelines were cited, reported and discussed.