Chekbox with filters

I have a stock query in C # that generates a report with reportviewer. I have a CheckBox that when I click on it it does not show me the items with a zero balance and when I unmark it it shows the items with a zero balance.

Since the query in SQL works perfectly, either passing parameter 1 to 0.

follow the code

private void btnPesquisar_Click(object sender, EventArgs e)
{
    string pSaldo = cbEstoque.Checked == true ? "1" : "0";

    this.SaldoEstoqueTableAdapter.Fill_EstProd(this.Estoque.SaldoEstoque, cbTipo.Text, cbArmazem.Text, pSaldo);

    this.reportViewer1.RefreshReport();
}

Follow the query in sql

DECLARE @SALDO VARCHAR(10)
SET @SALDO = 0

SELECT       
   SB.B2_COD, 
   S1.B1_DESC, 
   S1.B1_TIPO, 
   SB.B2_LOCAL, 
   (SB.B2_QATU - SB.B2_RESERVA) AS SALDO
FROM SB2020 AS SB 
    INNER JOIN SB1020 AS S1 WITH (NOLOCK) ON S1.B1_COD = SB.B2_COD
WHERE SB.D_E_L_E_T_ <> '*' AND S1.D_E_L_E_T_ <> '*' AND S1.B1_TIPO = 'MP' AND SB.B2_LOCAL = '01'
AND ((SB.B2_QATU - SB.B2_RESERVA) >= 0 AND @SALDO = 0) OR ((SB.B2_QATU - SB.B2_RESERVA) > 0 AND @SALDO = 1)
AND S1.B1_TIPO = 'MP' AND SB.B2_LOCAL = '01'
ORDER BY S1.B1_DESC

Rovann got query error

SELECT       
   SB.B2_COD, 
   S1.B1_DESC, 
   S1.B1_TIPO, 
   SB.B2_LOCAL, 
   (SB.B2_QATU - SB.B2_RESERVA) AS SALDO
FROM SB2020 AS SB 
    INNER JOIN SB1020 AS S1 WITH (NOLOCK) ON S1.B1_COD = SB.B2_COD
WHERE SB.D_E_L_E_T_ <> '*' AND S1.D_E_L_E_T_ <> '*' AND S1.B1_TIPO = 'MP' AND SB.B2_LOCAL = '01' 
AND (CASE 
     WHEN @SALDO = 1 THEN ((SB.B2_QATU - SB.B2_RESERVA) > 0) 
     ELSE ((SB.B2_QATU - SB.B2_RESERVA)>=0) END) 
ORDER BY SB.B1_DESC

erro 
Msg 102, Level 15, State 1, Line 13
Incorrect syntax near '>'.