# Searching for Clinical Trials

Updated over 2 weeks ago

Elicit allows you to search both research papers and clinical trials. This guide explains how to effectively search and filter clinical trial data.

## Switching to Clinical Trials Search

**From the homepage**  
- Select clinical trials in the search window when starting a Research Report, Systematic Review, or Find Papers workflow

**From the Gather stage**  
- Look for the corpus selector button (displays either "Research papers" or "Clinical trials")  
- Click the button to open the dropdown menu  
- Select "Clinical trials" from the options

**Note:** The clinical trials feature may not be available to all users.

## Available Filters for Clinical Trials

Once you've selected clinical trials as your search corpus, you can use specialized filters by clicking the "Filters" button.

### Has Results

Filter to show only trials that have published results. Useful when you want to see completed studies with available outcomes data.

### Phase Filters

- **NA** - Not applicable  
- **Early Phase 1** - Very early safety studies  
- **Phase 1** - Initial safety and dosage studies  
- **Phase 2** - Efficacy and side effects studies  
- **Phase 3** - Large-scale effectiveness comparisons  
- **Phase 4** - Post-market surveillance studies

### Recruitment Status

- **Active, not recruiting** - Study ongoing but not accepting new participants  
- **Completed** - Study has ended normally  
- **Enrolling by invitation** - Participants recruited by invitation only  
- **Not yet recruiting** - Study registered but recruitment hasn't started  
- **Recruiting** - Currently accepting participants  
- **Suspended** - Study temporarily halted  
- **Terminated** - Study ended early  
- **Withdrawn** - Study withdrawn before enrolling participants  
- **Available** - Expanded access studies

### Publication Year

Filter clinical trials by registration or publication year. This filters by the _most recent_ publish date, since trials can be updated multiple times.

## Limitations

- **Data Source:** Clinical trials data is sourced from [ClinicalTrials.gov](https://clinicaltrials.gov/), which primarily includes trials conducted in or by US-based organizations. International trials may be underrepresented.
- **Search Capabilities:** Unlike research papers, clinical trials search focuses on the trial protocol and registration information rather than full-text results papers.
- **Results Availability:** The "Has Results" filter indicates whether results have been posted to [ClinicalTrials.gov](https://clinicaltrials.gov/). Many completed trials may have published results in journals not linked to the registry entry.
- **Find Papers:** This feature is only available as part of Research Reports and Systematic Reviews. It is not yet available for Find Papers.

## When to Use Clinical Trials vs. Research Papers

**Use Clinical Trials search when:** looking for ongoing or planned studies, investigating specific interventions or drugs, understanding the research pipeline in a field, or finding trials for potential participation.

**Use Research Papers search when:** looking for published results and analyses, seeking systematic reviews or meta-analyses, wanting detailed methodology discussions, or needing peer-reviewed conclusions.

You can always switch between the two corpora to get a comprehensive view of both the ongoing research and published findings in your area of interest.