Variation of runTest methods of WebPage Test APi

WebPageTest General Discussion
1

I am using “GitHub - WebPageTest/webpagetest-api: WebPageTest API wrapper for NodeJS” for performance test ,

Currently below method performs only ‘1’ run and uses ‘Dulles:Chrome’ by default.

wpt.runTest(‘https://www1.XXX.com’,function(err, data) {
console.log(err || data);
});

How can i pass ‘runs’ and browser details in 'runTest method ?

any help is really appreciated.