Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Year | Competition | Venue | Position | Event | Notes |
| --- | --- | --- | --- | --- | --- |
| 2002 | Central American and Caribbean Junior Championships (U-17) | Bridgetown, Barbados | 1st | 5 km | 21:24.33 CR |
| 2004 | Central American and Caribbean Junior Championships (U-20) | Coatzacoalcos, México | 1st | 10 km | 43:21.99 |
| 2004 | World Junior Championships | Grosseto, Italy | 4th | 10 km | 41:01.64 |
| 2005 | World Championships | Helsinki, Finland | 8th | 20 km | 1:20:45 |
| 2006 | Central American and Caribbean Games | Cartagena, Colombia | 2nd | 20 km | 1:26:30 |
| 2007 | World Championships | Osaka, Japan | 4th | 20 km | 1:23:36 |
| 2008 | Olympic Games | Beijing, PR China | 15th | 20 km | 1:21:53 |
| 2009 | World Championships | Berlin, Germany | 3rd | 20 km | 1:19:22 |
| 2010 | Central American and Caribbean Games | Mayagüez, Puerto Rico | 1st | 20 km | 1:22:32 GR |
| 2011 | World Championships | Daegu, Korea | 15th | 20 km | 1:23:05 |
| 2011 | Pan American Games | Guadalajara, Mexico | 6th | 20 km | 1:25:00 |
Question:
how many times did they participate in the world championships?
Answer:
4