<?php
$grid = new ArtiGrid();
$grid->table('payments')
     ->modal(true)
     ->required(false)
     ->validation_required([
        'customerNumber'
     ])
     ->checkboxGroup("customerNumber", [
         "Obstetric Nurse (Delivery)" => "Obstetric Nurse (Delivery)",
         "Neonatal Nurse (RN)" => "Neonatal Nurse (RN)",
         "Physician" => "Physician",
         "Pediatrician" => "Pediatrician",
         "Anesthesiologist" => "Anesthesiologist"
      ], ",", 1);
echo $grid->render('insert');
?>