Ecolab Inc. ECL is slated to announce first-quarter 2016 earnings results on May 3. Last quarter, the company reported earnings of $1.22 per share, which missed the Zacks Consensus Estimate by a couple of cents.Notably, Ecolab posted negative earnings surprise of 0.71% on an average over the last four quarters, as shown in the below chart.Let’s see how things are shaping up for this announcement.Factors at PlayFor the first quarter of 2016, Ecolab expects Global Institutional, Industrial and Other segments to continue to show solid fixed currency growth, driven by investments made in sales and service force improvement.Ecolab projects adjusted gross margin at approximately 47%. Adjusted earnings are estimated between 73 cents and 80 cents. Unfavorable foreign currency is expected to affect earnings by 11 cents.Meanwhile, management expects results to improve in the second half of 2016.Despite headwinds like unfavorable foreign currency and Venezuela deconsolidation, we believe that a robust product portfolio, new product launches and an expanding customer base will drive organic sales. Meanwhile, the realization of targeted synergies associated with acquisitions will help in margin expansion.Earnings WhispersOur proven model does not conclusively show that Ecolab is likely to beat earnings this quarter. This is because a stock needs to have both a positive Earnings ESP and a Zacks Rank #1 (Strong Buy), 2 (Buy) or 3 (Hold) for this to happen. That is not the case here as you will see below.Zacks ESP: Ecolab currently has an Earnings ESP of 0.00%. This is because both the Most Accurate estimate and the Zacks Consensus Estimate stand at 76 cents.Zacks Rank: Ecolab currently carries a Zacks Rank #4 (Sell). We caution against stocks with a Zacks Rank #4 or 5 (Sell-rated stocks) going into the earnings announcement, especially when the company is seeing negative estimate revisions.Stocks to ConsiderHere are some companies in the broader healthcare sector that you may want to consider, as our model shows these have the right combination of elements to post an earnings beat this quarter:PAREXEL International Corporation PRXL, with earnings ESP of +2.25% and a Zacks Rank #1.Align Technology Inc. ALGN, with earnings ESP of +5.13% and a Zacks Rank #1.Becton, Dickinson and Company BDX, with earnings ESP of +2.49% and a Zacks Rank #2. Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report >>Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report ECOLAB INC (ECL): Free Stock Analysis Report ALIGN TECH INC (ALGN): Free Stock Analysis Report BECTON DICKINSO (BDX): Free Stock Analysis Report PAREXEL INTL CP (PRXL): Free Stock Analysis Report To read this article on Zacks.com click here.