Selecting radio button value in GEB

To select a radio button value in GEB using Groovy: in the page model define:

    static content = {
        selectRadioButtonOptionField {option -> $("input[type='radio']", name: "radioButtonName", value: option)}
    }

    def selectRadioButtonOption(String radioButtonValue) {
        browser.selectRadioButtonOptionField(radioButtonValue).click()
    }

I could not use the .value or = to select the radio button so I need to use the click method to select.