## 2 Materials and Methods
### Inclusion and Exclusion Criteria  
Results were included if they were peer-reviewed, full-text articles published in English in the last five years examining the 3 DPLM applications in LCR surgical planning and/or intraoperative guidance. The five-year publishing date threshold was selected to establish currency as 3 DP technology has advanced rapidly over recent years. Articles discussing 3 DP production methods/materials were included, as these factors directly impact 3 DPLMs' clinical validity and feasibility [28]. Articles describing 3D-printed liver phantoms for surgical simulation were also included, as 3D-printed phantoms in other specialties can provide tangible surgical benefits [28]. The limited original research present in the literature ultimately required the inclusion of case reports, which was a common practice in previous 3 DPLM reviews [20; 23; 24]. To ensure a suitability-focused review, articles were excluded if they concentrated exclusively on liver transplantation or non-cancerous pathology; if they discussed clinical education exclusively without carry over to surgical planning/performance; or if they focused exclusively on 3D bioprinting. Articles were also excluded if they were cadaver studies or if they were not available in English.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Search No.** & **Boolean Operator** & **Term** & **Field** \\ \hline \multirow{8}{*}{Search Strategy 1} & \multirow{8}{*}{AND} & \multicolumn{2}{c}{hepat* OR liver} & Title \\  & & \multicolumn{2}{c}{print* OR model*} & Title \\  & & \multicolumn{2}{c}{3D OR 3-dimensional OR three-dimensional OR} & Title \\  & & \multicolumn{2}{c}{“3D-printed” OR “3D-printing”} & Title \\  & & \multicolumn{2}{c}{tumour* OR tumor* OR cancer* OR carcinoma* OR} & \\  & & \multicolumn{2}{c}{malignant* OR metas*} & \\  & & \multicolumn{2}{c}{surg* OR oper*} & Any field \\  & & \multicolumn{2}{c}{and} & patient* OR segment* & Any field \\ \hline \multirow{8}{*}{Search Strategy 2} & \multirow{8}{*}{AND} & \multicolumn{2}{c}{hepa* OR liver} & Title \\  & & \multicolumn{2}{c}{print* OR model*} & Title \\  & & \multicolumn{2}{c}{“3D OR 3-dimensional OR three-dimensional OR} & Title \\  & & \multicolumn{2}{c}{“3D-printed” OR “3D-printing”} & Title \\  & & \multicolumn{2}{c}{“3D-print” OR “3D print” OR “3D printing”} & \\  & & \multicolumn{2}{c}{tumour* OR tumor* OR cancer* OR carcinoma* OR} & \\  & & \multicolumn{2}{c}{malignant* OR metast*} & \\  & & \multicolumn{2}{c}{outcome* OR patient* OR consent* OR duration OR} & \\  & & \multicolumn{2}{c}{time OR success OR morbidity OR result*} & \\ \hline \multirow{8}{*}{Search Strategy 3} & \multirow{8}{*}{AND} & \multicolumn{2}{c}{“medical imaging” OR “computed tomography” OR} & \multirow{2}{*}{Title} \\  & & \multicolumn{2}{c}{CT OR “magnetic resonance imaging” OR MRI} & \\ \cline{1-1}  & & \multicolumn{2}{c}{3D OR 3-dimensional OR three-dimensional OR} & \\ \cline{1-1}  & & \multicolumn{2}{c}{“3D-printed” OR “3D-printing”} & Title \\ \cline{1-1}  & & \multicolumn{2}{c}{print* OR model*} & Title \\ \cline{1-1}  & & \multicolumn{2}{c}{“3D-printed” OR “3D-printing”} & \\ \cline{1-1}  & & \multicolumn{2}{c}{print* OR model*} & Title \\ \cline{1-1}  & & \multicolumn{2}{c}{layer OR hepat*} & Any field \\ \hline \hline \end{tabular}  
* The asterisk (*) placed at the end of search terms above is a wildcard search operator which automatically includes alternate endings of that word in the search (eg. “hepat*” will include, “hepatbiliary’, “hepatcide”, “hepatectomy”, etc.).  
\end{table}
Table 1: Search strategies to identify suitable studies for inclusion in the review.