# Get pubmed data

## Introduction

This vignette demonstrates how to retrieve citation data from PubMed using:

- `get_pubmed_count()` — to retrieve the total count of articles matching a term.
- `get_pubmed_by_year()` — to get article counts by publication year.

These functions are part of the `risk.assessr` package.

DISCLAIMER: This feature only works if you choose a good R package name.

## Setting Your PubMed API Key

To increase request limits and improve stability, you can use an NCBI API key.

To add a PubMed API key (token), please follow the steps Here

    # Replace with your actual API key
    options(pubmed.api_key = "your_actual_ncbi_api_key")

## Load Required Libraries

    library(risk.assessr)
    library(ggplot2)

    package_name <- "limma"

## Total Number of Articles Matching a Term

    pubmed_count <- get_pubmed_count(package_name)
    pubmed_count

## Number of Articles by Year

    citation_data <- get_pubmed_by_year(package_name, years_back = 20)
    citation_data

## Plotting the Article Trend Over Time