Identifying IO bottlenecks in MS SQL

select top 25

    (total_logical_reads/execution_count) as avg_logical_reads,

    (total_logical_writes/execution_count) as avg_logical_writes,

    (total_physical_reads/execution_count) as avg_phys_reads,

     Execution_count,

    statement_start_offset as stmt_start_offset,

    sql_handle,

    plan_handle

from sys.dm_exec_query_stats  

order by

(total_logical_reads + total_logical_writes) Desc