function creatCalc(form) {
	var weight = Number(form.w.value);
	var age = Number(form.age.value);
	var cr = Number(form.Cr.value);

	if (!checkNum(weight,"WEIGHT")) {
		form.w.select();
		form.w.focus();
		return false
	}

	if (!checkNum(age,"AGE")) {
		form.age.select();
		form.age.focus();
		return false
	}

	if (!checkNum(cr,"CREATININE")) {
		form.Cr.select();
		form.Cr.focus();
		return false
	}

	if (form.wu.selectedIndex == 0) {
					//  What units for weight?
					//  0 = lbs
					//  1 = kg
		weight = weight * 0.45359237;
	}

	clear = ((140 - age) * weight) / (72 * cr);

	if (form.sex[1].checked) {	//  Is the patient female?
					//  0 = male
					//  1 = female

		clear = clear * 0.85;
	}

	clear = rounding(clear,0);
	form.clear.value = clear;

	return true
}


function checkNum(val,text) {
	if ((val == null) || (isNaN(val)) || (val == "") || (val < 0)) {
		alert("Please enter a value for " + text + ".");
		return false
		}
	return true;
}

function rounding(number,decimal) {
        multiplier = Math.pow(10,decimal);
        number = Math.round(number * multiplier) / multiplier;
        return number
}
function poundsAndKilos(form) {
	var weight = Number(form.w.value);
	if ( weight > 0) {
		if (form.wu.selectedIndex == 0) {	// 0 = pounds.
			form.w.value = rounding( weight / 0.45359237,2);
		} else {								// 1 = kilograms.
			if (weight > 219) {
				form.w.value = rounding( weight * 0.45359237,2);
			} else {
				form.w.value = rounding( weight * 0.45359237,2);
			}
		}
		form.wt.select();
		form.wt.focus();
	}
	return true;
}