Preliminary searches were done in PubMed to define useful terms for the search strategy. This revealed that searches could be made sensitive but not specific enough. We developed the definitions described below.

Search terms for types of participants: working at construction sites
The search term construction is truncated as construction* according to the industry name not as construct*, since many other things can be constructed for example, vectors or plasmids in the biochemistry field. The terms "construction industry" or "construction worker" are not used in order to make the search not too specific.

Many articles mentioned the word building instead of the term construction, which is why the term building* was added as a search term.

It is possible that there are articles including neither construction nor building. This is why the most important job titles (trades) were included in the search strategy used in the study by Koningsveld and Van der Molen (Koningsveld 1997). In addition we added the following job titles that appeared many times in the articles found in the preliminary searches: laborer/labourer and contractor.

The terms construction, building and job titles like carpenter are also used for other purposes such as a surname or in a company or street name (location), and that is why the search words concerning the population are followed by a search tag [tiab] (title abstract) or [tw] (text word).

Search terms for outcome: injury
The primary outcome in the search strategy was defined as an injury and the term is truncated as injur* to make it sensitive enough.

Also the terms accident and safety were taken into account. Accident was truncated as accident* to make it sensitive enough.

Search terms for interventions
Intervention in the search strategy was defined as any kind of intervention related to safety management, risk management or accident prevention applied to decrease the rate or severity of injuries. Terms resembling these kinds of interventions were selected for this part of the search strategy.

Search terms for study design
For study design, two search strategies were used to find (cluster) randomized controlled trials and prospective non‐randomized controlled trials or interrupted time series; for the discussion section the last strategy, search #7, will also be used to find before‐after studies and case‐reference studies. For randomized controlled trials we will use the strategy described by Robinson and Dickersin (Robinson 2002) and for non‐randomised studies the strategy described by Verbeek et al. (Verbeek 2005).