CREATE PROCEDURE proc_ToBeInitiate(
    @status varchar(50),
    @retVal int output)
AS
BEGIN
    select
        INITIATED_FOR, [emp name],
        INITIATED_by, REQUESTED_DATE,
        UPLOADED_LOA, UPLOADED_Bg_Check_Form
    from
        tbl_User t , tbl_INITIATED I, tbl_SUBJECT_FORM S
    where
        t.[Emp No] = I.[INITIATED_FOR]
        and S.[Emp No] = I.INITIATED_FOR
        and i.PROGRESS_STATUS = @status

    if(@@ROWCOUNT <1)
    BEGIN
        RETURN @retVal;
    END

    SET @retVal = @@ROWCOUNT
END
GO

[HttpGet]
    [ResponseType(typeof(ToBeIntiated))]
    [Route("api/ToBeInitiated/{status}")]
    public IHttpActionResult ToBeInitiated(string status)
    {
        var retVal = new SqlParameter() { ParameterName = "@val", Direction = ParameterDirection.Output, SqlDbType = SqlDbType.Int };

        var locstatus = new SqlParameter("@status", SqlDbType.VarChar);
        locstatus.Value = status;

        using (var x = new DB_BgCheckEntities())
        {
            IEnumerable<ToBeIntiated> toBeInitiated = x.Database.SqlQuery<ToBeIntiated>
           ("exec proc_ToBeInitiate @status,@retVal out", locstatus, retVal);
         //   var a = x.proc_ToBeInitiate(status,retVal);
       //   ToBeIntiated toBeInitiated=  x.Database.ExecuteSqlCommand("exec proc_ToBeInitiate @status,@retVal out", locstatus, retVal);

            if ((int)retVal.Value == 1) //this line generates error
                return Ok(toBeInitiated);
            else
                return NotFound();
        }
    }