As an investor, it doesn't pay to follow the crowd.

In this series, though, we highlight a possible exception -- the collective wisdom of our CAPS community. Read the next section if you're unfamiliar with our methodology. Skip it if you want to go straight to the results.

Why this crowd is different
Jumping into a stock because your rich neighbor did, or because you heard about it from your friend's uncle who used to work on Wall Street, or because CNBC has been talking about it nonstop is a recipe for disaster.

If there's one thing I've learned as a stock analyst, it's that any stock can be gussied up to sound like a world-beater. If there's a second thing I've learned, it's that being a smart person doesn't make you a good investor.

In the hands of a smart person with good communication skills, the never-were and never-will-be stocks sound like tickets to instant fortune. The ancient Greek philosophers made the distinction between rhetoric and knowledge. The former is convincing; the latter is true.

That's why we factor in track record in our Motley Fool CAPS community. We invite everyone to give stocks an outperform (akin to a "buy" call) or underperform rating (akin to a "sell" call) in CAPS. We then use those opinions to calculate a rating for each stock -- from one to five stars (five being the best). But -- and this is a big distinction -- we give more weight to the opinions of folks whose picks have performed well in the past.

The top 10 health services underperform calls
So, with that methodology as prelude, I present to you the 10 one- and two-star health services stocks with the most CAPS community member underperform ratings (I used a minimum market capitalization of $100 million and the proviso that it must be listed on a major U.S. exchange). Remember, stocks are rated on a five-star scale by our CAPS community, so one- and two-star stocks are consensus underperforms.

Company Name

 Market Capitalization (in millions)

52-Week Price Change

Price to Earnings (TTM)

CAPS Rating (out of 5)

Underperform Picks

ArthroCare (Nasdaq: ARTC)

        $684

43.9%

NM

*

148

DexCom (Nasdaq: DXCM)

        $709

54%

NM

*

116

Amedisys (Nasdaq: AMED)

        $706

(45.7%)

4.8

**

101

China Nuokang Bio-Pharmaceutical (Nasdaq: NKBP)

        $105

NM

8.3

**

68

Sunrise Senior Living (NYSE: SRZ)

        $136

5.2%

NM

**

62

Aetna

     $11,210

(7.6%)

7.6

**

58

Edwards Lifesciences (NYSE: EW)

      $6,515

85.1%

30.1

**

58

Align Technology (Nasdaq: ALGN)

      $1,235

20.3%

135.3

**

51

Insulet

        $566

51.8%

NM

*

41

Cyberonics

        $582

39.4%

7.9

**

34

Source: Motley Fool CAPS. NM= not meaningful. Price change from Aug. 28, 2009, through last night.

There's a barbell phenomenon in the P/E ratios of these stocks. Many have P/E ratios that are not meaningful because of negative earnings (or have earnings that are so low with relation to price that the P/E ratio isn't helpful -- e.g., Align Technology). On the other side, we have a few that have P/E ratios that are 10 or below. Either way, the CAPS community isn't impressed with any of these 10.

More CAPS members think medical device maker ArthroCare is an underperform than any other health services stock. Do you think it deserves this lack of love? Make your thoughts known in CAPS by clicking here. Or just go there to do further research on one of these stocks.

You can see the flip side -- the top-rated health services stocks by clicking here.