[Publications German-speaking countries in high impact journals: development and validation of a search filter]

Publications German-speaking countries in high impact journals: development and validation of a search filter Abstract.

BACKGROUND

The number of publications in journals with a high impact factor is an indication of a discipline's participation in international discourse. A search filter allows reliable and reproducible searches for specific publications.

AIM

Development and validation of a geographic search filter for publications by nursing scientists affiliated to German-speaking countries in nursing journals with a high impact factor.

METHODS

The search filter was objectively developed following several steps: (i) creation of a development and a validation set, each consisting of relevant and non-relevant publications, (ii) generation of the search filter by means of text analysis of the development set, (iii) internal validation based on the development set and (iv) external validation using the validation set. The validity was examined regarding several accuracy parameters, e. g. sensitivity, specificity, positive predictive value (PPV) and number needed to read (NNR).

RESULTS

The search filter correctly identified 22 of 30 relevant and 16 of 21 non-relevant publications in the development set: sensitivity 80 % (95 % CI 66 - 94), specificity 76 % (95 % CI 58 - 94), PPV 83 % (95 % CI 69 - 97). External validation yielded similar or better results: sensitivity 81 % (95 % CI 67 - 96), specificity 88 % (95 % CI 71 - 100), PPV 88 % (95 % CI 75 - 100). The NNR was 1.2 and 1.1, respectively.

CONCLUSIONS

The search filter has the potential to identify the intended publications.

[How do authors of systematic reviews restrict their literature searches when only studies from Germany should be included?]

INTRODUCTION

The use of search filters (e. g. for study types) facilitates the process of literature searching. Regional limits might be helpful depending on the research question. Regional search filters are already available for some regions, but not for Germany. Our aim is to give an overview of applied search strategies in systematic reviews (SRs) focusing on Germany.

METHODS

We searched Medline (via Pubmed) applying a focused search strategy to identify SRs focusing on Germany in January 2016. Study selection and data extraction were performed by two reviewers independently. The search strategies with a focus on Germany were analyzed in terms of reasonableness and completeness relying on the Peer Review of Electronic Search Strategies (PRESS) criteria. A narrative evidence synthesis was performed.

RESULTS

In total, 36 SRs (13 written in English) were included. 78% were published in 2012 or later. The majority (89%) of SRs utilized at least two different sources for their search with databases and checking references being the most common. 17 SRs did not use any truncations, ten SRs did not restrict their search to Germany, six SRs reported to have searched for German OR Germany. Only ten articles searched for the term Germany (occasionally jointly with the term Deutschland) without any use of an adjective such as German.

DISCUSSION

There is a high interest in regionally focused SRs. The identified search strategies revealed a need for improvement. It would be helpful to develop a regional search filter for Germany that is able to identify studies performed in Germany.