Aetna 2006 Annual Report Download - page 93

Report of Independent Registered Public Accounting Firm
On Internal Control over Financial Reporting
The Board of Directors and Shareholders
Aetna Inc.:
We have audited management's assessment, included in the accompanying Management’ s Report
on Internal Control Over Financial Reporting, that Aetna Inc. maintained effective internal
control over financial reporting as of December 31, 2006, based on criteria established in Internal
Control—Integrated Framework issued by the Committee of Sponsoring Organizations of the
Treadway Commission (COSO). Aetna Inc.’ s management is responsible for maintaining
effective internal control over financial reporting and for its assessment of the effectiveness of
internal control over financial reporting. Our responsibility is to express an opinion on
management's assessment and an opinion on the effectiveness of the Company’ s internal control
over financial reporting based on our audit.
We conducted our audit in accordance with the standards of the Public Company Accounting
Oversight Board (United States). Those standards require that we plan and perform the audit to
obtain reasonable assurance about whether effective internal control over financial reporting was
maintained in all material respects. Our audit included obtaining an understanding of internal
control over financial reporting, evaluating management's assessment, testing and evaluating the
design and operating effectiveness of internal control, and performing such other procedures as
we considered necessary in the circumstances. We believe that our audit provides a reasonable
basis for our opinion.
A company's internal control over financial reporting is a process designed to provide reasonable
assurance regarding the reliability of financial reporting and the preparation of financial
statements for external purposes in accordance with U.S. generally accepted accounting
principles. A company's internal control over financial reporting includes those policies and
procedures that (1) pertain to the maintenance of records that, in reasonable detail, accurately and
fairly reflect the transactions and dispositions of the assets of the company; (2) provide
reasonable assurance that transactions are recorded as necessary to permit preparation of financial
statements in accordance with U.S. generally accepted accounting principles, and that receipts
and expenditures of the company are being made only in accordance with authorizations of
management and directors of the company; and (3) provide reasonable assurance regarding
prevention or timely detection of unauthorized acquisition, use, or disposition of the company’ s
assets that could have a material effect on the financial statements.
Because of its inherent limitations, internal control over financial reporting may not prevent or
detect misstatements. Also, projections of any evaluation of effectiveness to future periods are
subject to the risk that controls may become inadequate because of changes in conditions, or that
the degree of compliance with the policies or procedures may deteriorate.
In our opinion, management's assessment that Aetna Inc. maintained effective internal control
over financial reporting as of December 31, 2006, is fairly stated, in all material respects, based
on criteria established in Internal Control—Integrated Framework issued by the Committee of
KPMG LLP
One Financial Plaza
Hartford, CT 06103-4103
KPMG LLP, a U.S. limited liability partnership, is the U.S.
member firm of KPMG International, a Swiss cooperative.
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