Why is my ADODB command output parameter null when the MSSQL stored procedure is populating it with an int? [duplicate]

I have an MSSQL stored procedure which explicitly sets an output parameter to a value. However, when I execute that stored procedure from an Classic ASP page using an ADODB command, the output parameter is null.

Stored procedure:

ALTER PROCEDURE [dbo].[recordResponse]
    @survey_id smallint OUTPUT, 
    @member_id varchar(10) OUTPUT,
    @response varchar(1000) OUTPUT,
    @comment varchar(1000) OUTPUT,
    @response_id int OUTPUT,
    @timestamp datetime OUTPUT,
    @status int OUTPUT
AS
BEGIN
    SET NOCOUNT ON;
    SET @timestamp = getdate();

    DECLARE @surveyExists as binary

    Select @surveyExists = 1 from surveys where survey_id = @survey_id;

    if (@surveyExists = 1)
        BEGIN
            insert into
                responses(member, [timestamp], response, comments, survey_id)
                values(@member_id, @timestamp, @response, @comment, @survey_id);

            set @response_id = SCOPE_IDENTITY();
        set @status = 200;
        END
    else
        set @status = 400;
END

Classic ASP:

    Set cmd = Server.CreateObject("ADODB.Command") 'Initiate the command object
    cmd.CommandType = 4 'Stored Procedure
    cmd.CommandText = "recordResponse" 'Name of the stored procedure

    cmd.ActiveConnection = connString 'Using which connection?

    'Add the parameters
    cmd.Parameters.Append cmd.CreateParameter("@survey_id", 2, 3, 0, 1)
    cmd.Parameters.Append cmd.CreateParameter("@member_id", 200, 3, 10, memberNo)
    cmd.Parameters.Append cmd.CreateParameter("@response", 200, 3, 1000, answer)
    cmd.Parameters.Append cmd.CreateParameter("@comment", 200, 3, 1000, comment)
    cmd.Parameters.Append cmd.CreateParameter("@response_id", 2, 2)
    cmd.Parameters.Append cmd.CreateParameter("@timestamp", 135, 2)
    cmd.Parameters.Append cmd.CreateParameter("@status", 3, 2)

    'Execute stored procedure
    Call cmd.Execute()

    Response.write "[" & cmd("@status") & "]"

This results in an output of [] whereas I am expecting an output of [200] or [400].

I have looked at various other similar threads and taken on board suggestions and solutions including iterating over the resulting recordset, but none have solved my problem.

Can anyone see where I am going wrong???